How about promotions? I think bitvest offer so low promotion since the first day while they had long campaign before.
Nowadays most casinos are competing to each other to provide the best offers/rewards/promotions so players are staying longer in the casino, bitvest need to compete as well IMO.
Bitvest is running with small bonuses since the beginning. But their token system is very interesting. Users can receive tokens from the faucet, by completing daily quests and from the chat rain. I was also playing there for having some free token balance when I was new to the gambling. I think they aren't going to bring changes in their bonus system, and users are habituated with that.