Very occasionally, the odds are strange numbers, or rather, numbers that "will definitely be a positive depending on how you bet". For example, "A... 2.5x, B... 3.4x, C... 5x" or something like that. In this case, if you bet with a ratio of A:B:C = 4:3:2, you will definitely be in the black. Even if each person can only bet one at a time, a family of three can cooperate and make a stable living. Doesn't this mean the bookmaker is losing money...? We ordinary people think so, but I think this is probably subsidized by the government. I don't know if it's a once-a-year tournament or a year-round casino, but if there is a local specialty, people will come. If people come, <...> taxes will come, and from the government's perspective, the money used for regional development is probably also set aside for that. If the total bet becomes extremely large compared to the upper limit of the subsidy budget, the odds may be reduced. There might be cases where casinos exchange non-cashable casino coins for prizes that have a zero purchase price, and they also recoup the money through lodging and meals. In any case, as long as it's not a rich person's charity, the bookmaker doesn't lose money somehow, so readers can rest assured. Slots in games within games often converge to a positive result if the number of attempts increases, but I think they're probably recouping that somehow too. People who win too much might be taken into a separate room and stripped, or the lifespan of people playing the slots is sucked out of them, or all the prizes are stolen, or whatever. Manga and games often feature gambling to guess the winner of some competition.