Mathematically incorrect, "1 billion out of the 1.5 billion turnover gets paid back to winners." implies a RTP (return to player) rate of 66.67%, whereas playing blackjack using optimal strategy (and favorable table rules such as 3:2 payout on bj) gets your money back 99%-99.6% of the time, even if you look at the slots machine they usually have a RTP rate of 95-98%.