Basically, the vendor said it shipped me the product but never did. However, it gave PayPal a tracking number which was for something delivered to my town. I waited several months for the vendor to make things right.

I asked PayPal and the person said there is nothing it can do. I did a charge back and the bank gave me my money back.

So no, screw the vendors and screw the payment processors. I don't owe them anything. It is their responsibility to do things right or get a charge back.