When I gamble, I do it because the pleasure I get from winning five dollars ("hah, take that, casino!") is slightly larger than the pain I get from losing five dollars ("oh well, who cares?").
I guess that truly rich people who gamble do it for similar reasons (though with numbers larger than five dollars). But poor people gamble because they (audaciously) hope to win enough money to change their lives. So I guess this explains why rich people play games with a high chance of getting a small payoff (blackjack, roulette) and poor people play games with a small chance of getting a huge payoff (slots, lotteries).
With the particular games you mentioned, you could also argue that rich people prefer more 'visible' games while the poor prefer 'invisible' games; Blackjack and roulette are done on or around a table with (possibly) many participants, whereas slots and lotteries are aimed to be a one-person experience.
The odds of winning the lottery may be 1 in 500 million, but for some people the odds of becoming rich by any other means is zero. If you define your goal as "becoming rich", and meet the above characteristic, then the lottery is no longer audacious or irrational.
I guess that truly rich people who gamble do it for similar reasons (though with numbers larger than five dollars). But poor people gamble because they (audaciously) hope to win enough money to change their lives. So I guess this explains why rich people play games with a high chance of getting a small payoff (blackjack, roulette) and poor people play games with a small chance of getting a huge payoff (slots, lotteries).