This is the reason slot machines are set to a specific Return to Player (RTP) percentage, why you see the 0’s on the roulette wheel and why craps just have such terrible odds.
By ensuring there is a house edge in each game on the gaming floor, they do just that – well, in the long run that is what they do. Their goal is to make money from each table, machine, and customer in the room. They need to make a profit from their customers (the players) in each area of operations. Despite how much fun they bring, casinos are all businesses.