Been out of the game awhile so let me get this straight...
I can have one crafter on my main world on my main account. On my second account I can create a bunch of level 1 characters on each world on the same data center as my crafter. With my alts I can travel to the world with my crafter, accept a bunch of crafted items and go sell them back on my alts world. I can then take my alts back to my home world and trade the gil back to my crafter?
Seriously? I think this is hilarious. Besides allowing people to sell items on every world on their data center, you've also given gil sellers free reign to move gil around data centers. For the price of a second subscription, I can create 16 retainers on 8 characters and sell 320 items? Yikes.