Expecting people to remember how a past event worked and therefore to have them assume that they better buy it now or it could disappear (as used to happen a lot with Gil deals) seems unlikely for EA. If that was the case, then what would be the point of the last chance offers? Because we'd know about it's likelihood based on past events and therefore not worry when the items first appear.
I think it is definitely sloppy programming. But why? I think that there must be a few different teams working there that are not sharing much code or procedures. The no timer thing doesn't happen often, but it's happened at least once before. I'm thinking it might just be by the same team. That or QA was on vacation during those times. That might explain the patch we got on a Sunday due to their oversight.