By calling a certain set of slots games “penny slots”, they make these games seem more affordable than they really are, which attracts gamblers who might have avoided nickel slots or quarter slots. Penny slot machines are one way that casinos use psychology to get an edge over players.
In fact, there are advocates of eliminating the penny and making the nickel the lowest denomination available. It’s literally the lowest denomination of currency that we have, and it’s practically worthless. In the United States, a penny is an interesting concept.
