I don't think it's that offensive.
I'm saying that it's likely that social cues are entirely different for them because of their situations. Just like any minority.
@Antarctic TermiteI get that. And I'm sure that's what most people think. But my argument is that their job is more important to them.
Edit: The bigger gap you see between yourself and others, the less you can empathize. The less you'll care when you have to tell them no.
My final point:
The woman in a wheelchair who checked my ticket last Friday didn't seem torn up about telling me that I couldn't bring in my fountain drink.

Her tone was entirely straightforward without a hint of sympathy.
For perspective, when she's not there, the other staff doesn't stop anyone.