I do think people forget that when they buy a product at MSRP, shipping and transaction fees are included in that price.
That's right. It shouldn't be any different when we are selling. It's a business transaction and the seller should factor PayPal fees into his/her price.
Seeing that "add 3% for PayPal" really irks me.
But, many times the seller has lowered his price slightly when I've asked. They know the 3% is out of line.