Ah, the younger generation.
By way of explanation: "Kiss my grits," was a term made popular on the TV Series "Alice," and was used often by the saucy southern waitress called "Flo" (played by Polly Holliday). Another of her favorite remarks was, "When donkies fly." I was responding in kind.
If we want to talk about things that fly . . . well, I saw all kinds of things fly that didn't normally fly . . . . . . . in the Seventies.