In all fairness, the lack of protection with an as yet untrusted seller is a bitcoin problem, and that's why many of us chose not to use it and opted for paypal/CC instead. I had the BTC and could have gotten the discount, but didn't because there wasn't enough trust yet and therefore required the protection.
So yes, solved one problem, by opening the door to another. BTC is a great technology, its just not done growing yet.
Escrow is the solution for the problem you describe (if they would have offered it). But I'll split the difference with you:
Require a BTC deposit to reserve a position in the queue and deduct it at fair value from the fiat payment. The deposit could live in escrow if so required.
This approach would have the added benefit of filtering out many fake orders and using BTC transaction speed effectively.
Right now it seems that the written terms changed without notice: the 8 hour window became a 5 day window. Which changes the risk profile quite a bit.
Agreed, TH could have made this process much more smooth with a (very) small amount of effort.