Remove the restrictions on credits (which shouldn't be there at all). Instead, apply restrictions to the purchase of a legacy bank. Make it a Cartel Coin purchase ONLY, and limit it to one purchase per account. That way, they can make a bit of money off of it, and enterprising individuals can't buy a few, and sell them on the market. Do they limit the legacy storage in some way like credits? Or Cartel Coins, for that matter...? I honestly don't know.