I think it's just like an office style environment for them in a way. If someone crashes at noon when they're supposed to scrim, it's a lot easier to go bang on their door than spam their phone and hope they wake up. When they need to go to a tournament, it's easier to buy 6 tickets from one airport to another, have them leave and arrive at the same time, and they all stay close together. There's no problems, because 1 person's flight got cancelled. There's no problem if something happens to one person. They all move at a unit, and while they're either all in or out, it's a lot easier to track and work with logistics wise. Plus, if they need to do something promotional for a sponsor, there's no flying a bunch of people to the same place, they're already together.

Also, these guys spend a lot of time with each other. They become close friends with each other. They probably want to live together for the same reason any other friends want to live with each other: they like each other. Living together for them is pretty cool, and can also help them work better with each other.