At least money falls out of a slot machine... This is just rolling a dice and seeing what number you get. Seriously, that's all it was for me... where are the battles people spoke about?
You'd be surprised. In the mobile app stores, there are slot machine simulator games that are licensed reproductions of popular physical slot machines but don't pay out any actual money. They play all the visuals and sound effects of a win that the physical machine would if the player spins a winning combination and award virtual currency for more spins. Despite this, they rake in absurd revenue from people spending real currency to play beyond the daily free allotment of spins.