One of the wheel lock nuts on my BRTs is stripped. What should I do? I don't want to put this in quick questions, because I want more than one person to answer, and I don't want it getting forgotten by other posts.

I don't get what you mean by stripped?

Yeah, I don't think a wheel can be stripped. They don't have threads, haha

Pics or better explanation?

...stripped wheels? Never heard of it. I've heard stripped baseplates & nuts, but wheels? Maybe you can tell us more about the problem.  

I meant stripped bolt, sorry. It's just keeping in the wheel. Now do you guys know what I mean?

pull the wheel towards you while unscrewing maybe

push the wheel against the nut, then unscrew with the tool while still keeping the wheel against the nut. The pressure should force the nut against the threads and make it unscrew. if it doesn't work, just give it a good tug. Your axle is stripped so you'll probably need to buy a new one.

Try to carefully pull the wheel against the bolt, sometimes the treads inside the bolt is weak and will give into the yanking. or if you have needle head pliers then put tape over the tips of them and pull on the bolt while holding the wheel forwards.