The point of the OP's story is NOT, "Why didn't I get my 4th set of pajamas? I'm entitled to unlimited pajamas!" So the cynical snark is way off base.
The point is "UA staff copped a terrible attitude and provided hostile service." All they had to do was say, "I'm so sorry, we don't seem to have pajamas this trip--I'm not sure why that's printed on the menus. If I run across any, I'll bring you some."
Sounds like an EWR-based crew for sure.