The 'How' on how people get the gil is irrelevant. The person selling the items doesn't care if you got a windfall from selling a lucky break item, or if you spent the money on tokens, or if you bought it from a gil seller. He only cares that you now currently have it and want to buy his item.
No one is buying anything WITH real money. Once it is in the game, it is a commodity that people will buy, or not buy. You are not handing the crafter a fistful of cash and getting items from them.
No, it would mean that individuals who buy the token would have the opportunity to spend the gil on whatever they wanted. They could put it to a house fund, they could put it to buying gear, they could put it to upping a craft or simply making sure a minor class they're leveling has adequate gear, or it could all go to teleports and buying mounts; or it could go to someone gifting the game time to a friend and no gil is transferred anywhere. You don't know, you're using the worst case scenario as the basis for what everyone will be doing.
Tokens would be at the whim of the market. If one person decides to sell their token for 1mil gil, but the person that comes in afterwards decides they want to sell theirs first, so they put it up for 900,000gil.. and then the third... That's how a market works. You would have people competing to sell these tokens; but you assume that they will stay high and people won't fight to sell theirs first, as if they all agreed on the price before hand.
And then they'd see that they won't have nearly the sales they'd like, as more gil per item means less purchases. Less purchases means less net gil for the seller.. and prices will fall back to a comfortable level because selling two items at 150,000gil is better than selling a single item 250,000gil. Markets stabilize based around reliable sales, not hopeful windfall purchases.
I can tell you one thing, most people who buy the tokens won't just waste their money on frivolous purchases, because they are spending their hard earned money to buy these tokens.