... but they could also offer the option of doing that, but alternatively just letting you transact the game to another Steam user directly, using the in-store currency (with an x% shaved off the top) for the cost of Steam basically working as an escrow service (to guarantee you haven't done something like converted to a key and then sold that key twice).
If doing so is fully compliant with the law, I predict that's what they would do (and it's probably worth the cost to them to pay the lawyers to argue that's fully compliant... ;) ).
... but they could also offer the option of doing that, but alternatively just letting you transact the game to another Steam user directly, using the in-store currency (with an x% shaved off the top) for the cost of Steam basically working as an escrow service (to guarantee you haven't done something like converted to a key and then sold that key twice).
If doing so is fully compliant with the law, I predict that's what they would do (and it's probably worth the cost to them to pay the lawyers to argue that's fully compliant... ;) ).