I view this as a feature actually - because it simplifies the protocol and creates a opportunity for e.g. two types of service on top of the bitcoin protocol (which already exist today for fiat currency txs anyway):
1. Sites tracking trust/reputation for merchants (so you can choose to only buy from merchants with good trust/reputation).
2. Bootstrapping a new merchant by covering e.g. undelivered products by refunding customers until the merchant has reached some level of reputation.
There will still be many customers happy to pay e.g. 2% txs fee to some payment service company so they can get refunds on top of bitcoin txs. And if you don't want a refund possibility you can simply use the protocol directly through a bitcoin wallet to pay directly to save the tx fee.