After a few weeks the craze will die down and people will begin purchasing things off the MB again.

Even though I beg to differ about the economy taking a hit. I know a lot of people that were taking advantage of Bronze Triad packs being 520GP, and being able to consistently keep buying 500GP, winning a match or two, buying a card pack and repeating. Multiple times to try and get the rare Behemoth from the pack as opposed to farming it.

This is actually better for the economy imo because gil inflation was already so bad, this is actually removing gil from players hands, and just maybe add a bit larger sense of value to the things we can purchase from other players.