I know Valve would never do this…

Surely if the items hold no real-world value, putting it on hiatus for an indefinite amount of time would be the answer. The casinos which depend on Valve can’t really sue the loss of the feature, as it’s always in Valve’s purview to remove it at any point from the game & platform.

If they made it a limited time feature in CSGO in a year, they would still achieve the “stickiness”.