While I agree with you to an extent, there is such a thing as people doing things like twisting apologies as admission of guilt, or taking advantage of a people pleaser to try and wangle a comped meal out of a minor infraction.

Sure the customer service people who are rude back get more abuse in return, but then it turns into a game of "Can I get this empoyee so worked up that they do something so bad their manager is forced to give me a freebie to smooth things over."

The best way I've found to deal with them is to be polite but firm. Nice, but not yielding an inch. It leaves them no weakness to exploit and no rage to also exploit.