“mummy, I want one of those”
#bestcommentever
Amusing in a different way, I also overheard this today:
“if you can ride a bicycle no handed you can ride a unicycle” 
I’ve gotten that quite a lot, but usually when I’m pushing it; not actually sitting on it. In the situation you described, I think the funniest reply might be “No.”
I think the very first compilation of “Snappy Comebacks to Stupid Comments” included that question. One of the responses we offered is “I’ve had to have one of these ever since my operation.”
Love it.
“Can you ride that?”, is pretty much the standard question when I’m walking with a uni. This is of course followed up by, “Show us”. Riding doesn’t usually impress them much. Better response if I mount and hop about but that is hard on a big wheel.
I have occasionally been tempted to reply, “No, I just walk around with it to look cool”, but isn’t really going to work as a comeback.
I think that question while riding begs for a response of “no”. I usually respond with, “No, I just fake it with authority.” Almost always, they just freeze with a puzzled look, as if their brain is overheating from trying to figure out how anyone could ride on one wheel, much less fake doing it.
LOL!! OK, that will definitely be my go-to response from now on! 
after riding yesterday afternoon as I dismount and start walking around for a min
I guy walks up and say’s Is this your first job being a clown
I looked at him and replied, No they won’t take me because I can’t juggle
You could ask him the same question…
Not at all, we use that (or similar) all the time! Just on Saturday, my friend offered “No, we’re posers.”
A response I probably wouldn’t have thought of at the time:
“Yes, apparently you got fired and they were desperate.”
Sometimes people will say “Do a trick!” When I’m not in the mood, sometimes I’ll say “You first.” And on a few occasions, I’ve gotten surprises by people who then demonstrated some interesting stuff they could do! But mostly not.
I rode up behind a liitle kid on training wheels with his dad. As the boy looked over his shoulder his eyes got huge and he crashed into the grass and started laughing. While laying on the ground and laughing he yelled out, “HE BLEW ME AWAY” and continued laughing.
Thanks for that - a comment I get occasionally, and I’m usually happy to oblige (it doesn’t tend to be used in a negative way and I sometimes enjoy showing off!), but that seems like a great response. Possibly a response best given whilst doing a “trick” whilst pretending you’re not doing anything special (bunny hopping is usually sufficient to satisfy that request) 
Yesterday I got a dry, “Very commendable,” from some middle aged bloke.
Also, a “Sweet!” from a teenager on a bike.
Yesterday I got my first comment ever for NOT being on my unicycle. A lady walking her dog asked me „where’s your bicycle?“ when I was jogging one of my more standard unicycle routes.
(This leads to the question, whether some people think that a unicycle is just a special type of bicycle. At least special enough to mention the fact that you’re not riding it when they see you without.)
(When my main sport was running many years ago, sometimes strangers asked me why I‘m riding a bike instead of running as usual.)
Today a neighbor witnessed me riding my Hatchet over some bricks I laid on the ground randomly and bursted out „what a monster!“.
(She hadn’t seen my Hatchet yet)
It’s comments like that that stopped me riding in a kilt.
The impressive thing about that is that this lady recognized you without the unicycle! I’m pretty sure if I showed up on our local bike path on a bike, nobody would notice anything. :o
Ow. Just the thought of riding “commando” in a kilt – have you done it for any length of time?
Not exactly a comment…
My wife and I biked to her mom’s yesterday, and upon arrival my mother-in-law said “I didn’t even know you had a bike!”
Wiley Coyote
Fun one today. Riding along and from behind I hear: “So, I guess you are a fan of Wiley Coyote’s favorite shopping center.” Seemed especially appropriate for me since I was headed to ACME Coffee Roasing afterward to further jet propel my day! 
!
Try, try, try again…
I was riding along a canal tow path earlier in the month when I UPDed after someone passed me on a bike. I was pretty out of breath at the time but thought I’d best get back on and continue rather than wait.
After the third botched freemount while trying to get my breath back, a passing woman from a couple out with their dog remarked, “If at first you don’t succeed, and all that”. I didn’t have a witty comeback at the time, but my first thought was along the lines of ‘with this malarkey you have absolutely no idea how right you are’.
A few days ago (and sorry, not quite the usual quote thing!):
“do you think it’s a good idea to ride that through here?” - I was on my giraffe in a fairly busy pedestrianised area (we’ve discussed this elsewhere, I’ve done a lot of practice and 100% confident in my skills to avoid hitting anybody), the obvious implication being that he thought it wasn’t!
I did have to work hard not to laugh as the discussion progressed - I mean he’d presumably just watched me manoeuvre through a narrow gap with tight turns and I was sitting there idling whilst talking to him (he caught me as I was idling waiting for a bit more room). The point he completely lost the argument IMHO was when he asked what would happen if a dog ran out in front of me* - as I pointed out, that would be an issue with a dog not being under control, not anything to do with my choice of transport. I asked him if I didn’t look like I was under control, and he said he wasn’t sure, which was the point I really had to restrain myself from laughing as I idled away! Oh, but the best bit was that I asked who he was and he said he was from Worcester BID (a business improvement thing) - I then suggested that it was a bit more of a pain than usual with all the cars parked in the pedestrianised area, doubtless he was there as part of the organisation of the “car show” (an honest opinion of mine - I did think WTF are all these cars doing here and that however “important” it might be for business that’s no excuse for clogging up the ped area when the council should be doing more to encourage people out of their cars).
- arguments about avoiding dogs which run out in front of you always lose IMHO - dogs are supposed to be kept under control, yet it seems there’s more tolerance for people not bothering with that than for people doing perfectly legitimate things trying to avoid them. Had another one yesterday when a woman had a huge number of dogs all off leads on a shared use path, was coming towards me so must have seen me plenty of time in advance, yet I had to call out as I approached to get her to pay attention. She still hadn’t managed to clear any space on the path as I came up to her, so I just managed to squeeze past right on the side - at which point she gasped presumably because she was suddenly worried about her dogs because I’d come quite close to a couple of them
For those in different countries where things might be different, there’s a clear instruction in our Highway Code to keep dogs on short leads on such paths The Highway Code - Rules about animals (47 to 58) - Guidance - GOV.UK
I’ve seen this too a few times when just riding on the cyclepaths, some mostly women that look at me all scared, certain that I am going to fall against them or something. Some also have to mention that to their fellow riders. “It shouldn’t be allowed to ride on 1 wheel.”
Yesterday an older guy riding with his buddies on racebikes told me to keep both hands on the steer ( was riding with a T-bar and for safety had 1 hand in the air. As I put my other hand on the bar as well, they all laughed ). I thought it was quite funny.