Not hilarious is that people like this (maybe not to this degree of rude/snarkiness) get hired all the time and seem to stay in jobs too! People have complained about the receptionists at my dermatologist's office for years. They still work there with the same attitude.
I often wonder if they are related to or close friends of the owners. In one case, I just cannot imagine it. She seems like she came straight out of prison or something. If I'm not mistaken, employers get subsidies/tax breaks for hiring former felons, no? My personal belief is that her bad manners probably just don't matter, as dermatologists are in short supply (they are one of the highest paid types of doctors) and business profits just aren't affected. Maybe they pay her a low wage and don't mind the trade-off. Who knows. I just know very rude people seem to stay for years at some jobs.