Speaking for myself, I'm not generally in the habit of "jumping on people" until they start getting snarky.
it's called consequential response. Dickhead wants to display even a modest display of cordiality, he'll see no response. You want to allow people to shyt on you, be my guest.
AKA the "but he started it" excuse.
You know, you are not required to give a flying fu*ck what anyone says. Just FYI.