I’m at Edmontons Capital Ex, which has a casino section with 80 machines or something. They were grouped by “price” in to 1, 2, 10 and 25¢ sections. I put a bill in the 2¢ one, but each play was 40, 80, 120 or 160 credits. To me that makes it an 80¢ machine, so why the 2¢ label?
To sucker you. It’s like how the nutrition label on a candy bar divvies it up into 2 or 4 servings, so that the per-serving information can appear lower.
It’s also nostalgia as penny slots and the like used to be the norm.
Not all of them do. Each machine has a certain number of paylines to be played . ( I’ve seen anywhere from three to around 250) The denomination of the machine is the minimum bet per line. The OP was apparently playing a game which required all 40 lines to be played at a minimum bet per line of .02 per line. Other games let you play fewer lines, even one line so that you can actually play for .02.
I suspect that the reason that penny and nickel machines still exist is not because of nostalgia, but to allow the games with the huge numbers of paylines. Fewer people will play 256 lines at .025 a line