There's one problem with bitcoin. sometimes absolute freedom is too much freedom. People need to feel "safe" about their money, even if it is just an illusion. Banks, Paypal, etc give people that safety. Bitcoin on the other hand, where every single transaction is final and there's no central authority, makes most people a little uncomfortable.
Yes, the chargeback option that banks offer through credit cards is one that BTC can't offer in case of a undelivered product or other issue with the sale. Potentially this could be overcome by some kind of consumer escrow function. It would likely not be handled in a decentralized manner.