When you buy those tc boosters. Do they only work in official servers or globally?

They work for every game you play.

So if you bought a 50 tc booster, every time you won a match, you would get 50 tc. Doesn't matter if you're playing in Semi-Pro Aikido, a private room, or tournament.

I'm pretty sure they work in any room.
E: Ninja'd

by all servers. when you win you'll get the amount TC's of the booster you boughed.

Everyone's right. You can use the boosters in any servers as long as you win. Its still the same as an item that you activated to appear in game.

sweet.