I had one that came with a learner uni. Still have it, and still use it for my Kris Holm 20" that sits in the corner. So yes it is useful for me (also it puts it on display!)
I used to have a nice, chrome-plated Miyata stand. It was much classier, and more stable, than those tiny black stands. Those are just a UPRD waiting to happen (unplanned riderless dismount).
I also use hooks in the garage, or otherwise lay them down so they don’t fall down. But stands were good back when I used to do shows…
I have mine on my guitar stand, because when coming back up to university I couldn’t carry the guitar and the unicycle, so I opted for the unicycle and the guitar stand ended up empty!
I would say +1 on the guitar stand but it can only accommodate smaller wheels. The little black stands work and have a small footprint but they are a hassle to use so I don’t. Haven’t brought myself to throw mine away yet though. I use hooks.
I use the little black stand when I keep my uni inside because I cannot hang it from the ceiling and the stand can be moved. It is a nice way to display my uni also.