That's a risk they bear. They need to come after the seller for their money. Since they probably have the owner's social security number and they definitely have their bank account, it's not a good idea to stiff a financial institution or intermediary. That can damage your credit.
If you have a charge back, you need to deal with it. Trying to stiff Paypal is not going to get you out of hot water. In fact, you could be in bigger hot water later by not dealing with it. If you accept a credit card payment from Paypal, you need to accept the risk of charge back. If you are not willing to accept that risk, don't accept the credit card.
If you accept a credit card payment and stiff paypal because of a chargeback, I hope they come after you and kill your credit so you can never take a credit card payment again. It's people like that who cause transaction fees to go up for everyone else.