Ditching those surly, tip-hustling airport wheelchair pushers is an art form for us. It's harder to do on departure -- you have to get the chair to begin with -- but on arrival, when the chair is waiting at the jetway, I'm not going to stand there and wait for a pusher to show up maybe 20 minutes from now, maybe never.
Danger! Do not self-push a wheelchair on a moving walkway. If the chair won't go over the bump at the end of the walkway, you risk a pileup of human bodies behind you.