Many sites even have build in bots that do this for you. All designed to make you wager more, because your total wagered amount is the only thing the site cares about. The more you wager, the more the house earns.

Running it at a low multiplier is a terrible strategy when it comes to house edge: you wager high amounts for small profits! Doing the same with much higher multiplier gives you a much smaller house edge. I call this the Landen strategy, named after the guy who successfully used this for months at Rollin. See this spreadsheet. The win chance on each run is very high, that's why it can last for months if your bankroll is high enough.

It's exactly what was to be expected. Some kid thinks he can beat the house with Martingale.
Isn't that the first thing any starting gambler does? Start small, double when you lose, think you're really smart, and profit a bit?