Normally, when I list something, I do not expect to be compensated by paypal. I don't advertise as such and I don't want to be bothered with it. As a seller, paypal sucks. Paypal is buyer convenience. That's my opinion, like it or don't.
If you ask if paypal is an acceptable payment method (instead of just assuming so), I might accept. I might also ask you to cover the fee's. This is called negotiations. If you don't agree with my terms, either counter, or say "no thanks". There's nothing illegal or unethical about negotiating terms. It's part of life.
P.S. Petty almost always swings both way's. Funny how often people miss that part.