For Pokerfans who would like to try their luck and skill without risking their money, these sites do give real money to free entrant of the tournaments.
1. SWCPoker.eu - Free tournament every hour with 1000 satoshi reward. Quarantine special free tournament twice a day with 20,000 satoshis each. And other free tournaments for high Krill users.
2. Poker.com - Free tournament twice a day with 25,000 satoshi rewards each.
If you know any more keep on adding.
These gambling websites would surely gain popularity for doing that BUT they need to at least add some more verification for users to play there continuously. That may only be a small amount but people already view it as a chance to earn more which is nice for gambling websites.
I think only a few gambling places can still provide bonuses like that and if you know there are still many gambling places besides poker that can provide a lot of bonuses in the beginning specifically for new users or players who register using a valid email.