Yeah, you only had to pay 50% to get a batch-1 order submitted: but you needed to pay the other 50% before they'd ship it to you. Those long-tail people probably only sent half as a deposit... so had to go scrape up more BTC as soon as they saw other people were getting shipping notifications.
No, batch #1 customers were expeceted to pay in full. They probably honored a few orders that weren't paid in full right away, but the 50% option was not offered until batch #2.