IIN that I think these compliments to the disabled are patronising?

Exactly! Treat everyone who is an adult like an adult unless it later becomes apparent there's some reason you shouldn't.

On a similar note, I have a friend who uses a wheelchair and when she has a can of coke or something, she usually rests it on the arm of her wheelchair (while holding onto it). She was sitting outside a shop waiting for her friend to come out and when she looked round, an old lady was putting coins in the coke can. She'd thought it was a charity collecting tin simply because she associated people in wheelchairs with charity.