i think common courtesy is to let the chair go, BUT, an airport makes all bets off IMO. ATL is simply brutal to go from gate to gate, heck, its a small metropolis in there. it was late and everyone at that point is inconvenienced. if somehow they could've contacted your next gate to let them know your situation, that may have helped.........but i dont think airlines have this capability.
the other thing is this......and i'm trying not to be rude, i find that many people, not all, getting rides and wheelchairs and such in airports don't seem handicapped. some seem fat, some seem old, some seem other. i am not asking you to ascertain each person's disability, but air flight is a priveledge, not a right and i don't think its fair that the greater good is inconvenienced for any one person.
i took a flight last month and they announced no peanuts because someone had an allergy. well, i don't like sitting next to someone that reeks, but i don't get special treatment.
long story short......you do your best and make a call. i hardly think anyone else would give a second thought to being rude in an airport though.