This is similiar to my opinion on all those outcries of "Only playing it because Pewdiepie, or So-and-So played it".
It's a popular game or sometimes a fan suggested game (probably from someone who is also a fan of someone like Pewd and saw him play it and suggested it to another person they watch) and thus many people play it at the same time.
Since this is a South Park game it feels like that episode where the one kid keeps saying "Simpsons did it!" every time Butters comes up with some sort of plan. Just because someone else did it before, doesn't necessarily mean the person after is copying the person before.