Let’s ignore the overuse of pronouns. Let us also pretend that the writer used “not” instead of “never.” We should avoid asking why “thyself” is even there (maybe this was a romantic Quaker-themed restaurant?).
We should especially overlook that this black woman (judging by handwriting and tone) had such a profound inferiority complex that she felt compelled to project her grasp of the English language to a waiter.
There is a bit of unnerving social commentary here. The woman is not telling the server that he morally erred. Rather, his failing was in the presentation. The surface, and not the substance. This woman is giving the waiter helpful pointers on how to maintain the facade of equality. This is America’s compromise between Civil Rights and Boomer narcissism, where racial and cultural distinctions, interactions are reduced to something akin to a tea ceremony.
…But none of that is particularly funny, and I don’t do snobbish pandering. So instead let’s point out the obvious, hilarious, and utterly self-defeating nature of this picture.
> “Do not assume that because we’re black, we won’t tip!”
> Doesn’t tip.