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 Termite]

I 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. :lol Her tone was entirely straightforward without a hint of sympathy.

For perspective, when she's not there, the other staff doesn't stop anyone.