Yeah I used to think the same as you but the 6 month charge back warranty was the killer blow for me. Until 6 months have gone by you never know for sure whether you will have your money removed. If you are a regular seller then unlikely you will have unlinked your bank account/cards so it will come as a bolt out of the blue.
You aren't safe until 6 months is up.
But like I said, on the other hand eBay is by far the best place to buy stuff. Hell even ocuk doesn't give a warranty as long on its b grade stuff!
You don't have to unlink your card and bank account, you just need to make sure you don't have a PayPal direct debit set up.