>>544748413
It's trivial for Steam to figure this out. They just look at conversion rates for your game and check the accounts that bought it and if the data doesn't fit normal ranges they conclude it's fake and disregard for algorithm purposes. For the same reasons it's not worth it to have botted reviews or even reviews by friends. Steam knows what's the average review rate for a game, how often any Steam user leaves reviews and how much they played any game.