I think it all will depend on how gambling is classified. Maybe it should be taken into account for the rating, if nothing else. If it has gambling, make it a T or equivalent rating. Put it on the back of the box, just like violence or alcohol. It's far too late to make it go away, but at least that way, it's noted, and hopefully parents or the players can make a decision about it. Does anyone remember the casino in pokemon red and blue? It's strait up gambling, albeit without the use of irl money, but it was just as addictive as any other form, and it wasn't mentioned anywhere as a warning.