A couple ways that I observed:

1. A bright, stimulating environment with lots of color, noise, lights and music to make you excited and cloud your thinking.
2. Free drinks to lower your inhibitions.
3. Few (if any) windows or clocks so you lose track of the passage of time.
4. A new innovation in my day (the mid to late 1990s) was the penny slot machine. You think you’re only playing for pennies, but I saw people routinely play ever increasing numbers of pennies on single spins without realizing exactly how much they were playing. People who were normally nickel machine players (betting between 5 to 15 cents a spin) would soon be betting 20–30 or more pennies per spin.
5. Comped meals and rooms based on amount of game play.
6. Predominately (attractive) female dealers at the blackjack tables since men are most attracted to blackjack and studies have shown that men will bet more and take more risks in the presence of an attractive female.

I’m sure there are plenty of other ways that I didn’t notice. I’m sure the casino industry has had extensive studies done on how to get people to gamble more.