Casinos will allow any bet spread for the simple reason that for now there’s no proven method that can beat the house edge. Even when they ban card counters in
blackjack, they still let them play roulette because they know it’s basically unbeatable.
The only “winning” method is if you got an insane amount of money and just keep doubling your bet every hand. Like, bet $1 and lose, then bet another $1 and lose, then $2, then $4, and so on until it’s huge amounts. Math wise, at some point red or black has to come.
And if it doesn’t… I’d switch casinos, cause there’s probably something sketchy with that wheel lol.