It's now illegal to purchase an old baby crib, but you can give it away free with the purchase of the mattress. Seems odd, but that's what happening.
Heh, that's an old trick that ticket scalpers tried ... and the reason they use that is not necessarily to make them less likely to get busted, but actually to make the buyer feel more comfortable about making the purchase. (which is really bizarre, because buying a ticket above face value is not against the law, just selling the ticket above face is where the problem arises in most jurisdictions.)
Here's an example:
But Bitcoin is different, .. it isn't against the law to trade. At some level of trading it may become necessary in some jurisdictions to register as a money service business but if you are describing how miners can sell a few BTCs on ebay, I hardly would think that would apply.
So it is simply a matter of PayPal's user agreement prohibiting the use of PayPal's payment network when trading bitcoins. And as long as you as a seller aren't relying on PayPal to help you should a chargeback occur and don't mind them freezing your account and holding any funds that you had in the account (or doing a clawback against your bank account even), sure -- your idea should work just fine.