Maybe I'm missing something, but why is the last shirt printed more expensive than the first? Exclusive items with a lower item number are generally more valuable.
Why don't the timed items revert to a regular item once the timer is expired. Remove the grey background, basically.
I don't think you can really think of them as #1/100 like an art print. The increased price has more to do with the relative scarcity of the item when it was purchased.
Well, I guess they're going on the assumption that no one would purchase a more expensive shirt when a cheaper one was available. I see your point, though, and it does kind of negate what I said.
Why don't the timed items revert to a regular item once the timer is expired. Remove the grey background, basically.