I'll echo what others have said -- that dude is a shining example of what polishing a turd can accomplish. Pretty on the outside, but still, just a hunk of shit.
I'm assuming that the worker wasn't totally deaf, and could understand at least most of what people wanted, and could communicate well enough verbally that like, ASL interpreters weren't needed.
That said, it is a bit weird, and I have to wonder who at the USPS decided that was okay under the ADA's reasonable accommodation rules... it toes the line pretty closely. I'm glad this worker didn't have an issue with it, and things work well with her.
But fuck Adam for being upset by the minor inconvenience. He seems like the kind of douche that wants to hide the disabled people away from public view. Ass.