I think it only says it if you move from a location where you CAN play triple triad to one where you CAN'T. But that's a bit beside the point. You can go to Character Configuration, select the icon with the speech bubbles in it (Log Window Settings) and in the General tab, scroll down to Log filters. Click on the log tab which you want to change, and at the top of the Announcements tab there's System Messages. If you disable those you won't see the Triple Triad thing, but you'll also not see some other system messages like if you've entered a sanctuary or not.