These days I drop maybe a roll of quarters in slots
if I've gone to a casino to eat, otherwise I stay out of them. Whether the casinos near me would admit it, their payout rates were cut drastically after a year or so. A friend and I were getting monthly "match play" coupons for about a year and we would go over, eat, and play the amount of the match play and always came out ahead (often double or more) or broke even. Usually at some point we would be able to put our original money back and just play on what we were ahead. Never during those trips did either of us lose money. Since those promotions stopped I rarely get back more than 50 cents from a machine and usually nothing. 50 cents for $30 is not a very good ROI
Casinos are entertainment, not investment opportunities for the cash-strapped. Go to them, enjoy the shows or other attractions, eat, drink, and drop on the table/machines only what's in your "entertainment fund'.