Could be in any context. I do it a little on UFC fights but that’s a relatively low amount and I can afford I to lose any time I do. It seems like it’s becoming a really wide spread problem though, at least in the US. At the same time I don’t see why it should be illegal. Granted I also don’t think any drug should be illegal.
I worked in a casino in the late 90’s. I dealt with supplying the coins and payouts for all the slot machines. When a machine would have a jackpot I could have the payout and paperwork printed and waiting before the techs could get to the machine. Everything would show up on my computer screen, including when there was a machine fill done.
Now ask yourself what prevents the machines from being “tighter” or “looser” at the push of a button or click of a mouse.
Every single game is designed to make the house a profit. The only way to truly win at gambling is to own the casino or not play.