Tonight I'm out of home, but I hope there will be a lot of poker tournaments (I think without buy-in would be easier to promote that kind of things)

Poker without buy-in is not poker. To be honest a buy-in under a dollar isn't either. Make it at least BTC 0.05 to be worth the time to play.
I'm on the same way as you, but I was thinking about this tournament as a promotional event for new/future users... if they have to put some money for nothing they'll not take same interest in it
