Media Dis&Dat and Bad Cripple have recently posted on the terrible state of airline service when disability accommodations are needed or when wheelchairs are involved. Wheelchair Dancer's also posted on this topic in the past. The humorist in me wonders if airlines like to see how much mandhandling a wheelchair can take before damage occurs or how long it will take for someone's patience to wear thin when the wheelchair isn't forthcoming.
One possible backup is Scoot Around, a service that will deliver wheelchairs and scooters to the airport when there is damage, at the airlines' expense. The manual wheelchair featured is a hospital clunker, but it's possible they might have others. The availability of such services may not reduce ground crews' willingness to be careful with chairs, but it's good that backups are becoming more available. It might be worth keeping their information handy for an emergency.
For those who can get by with a transport wheelchair at the airport, they can have rented wheelchairs or scooters to be delivered to the hotel. I'd have some concerns about pain and pressure sores from bad seating with a brand I hadn't tried, but that could help with some of the airline hassles. Transportation's always difficult to figure out, of course, whether it's getting an accessible van or trying to get shuttles that will take a wheelchair or scooter (what law?). Without a wheelchair or scooter past the airport, I'd feel vulnerable. But again, at least options are increasing.