Because it brought you here, it can take you back, or the people you get to know. Or it can do any number of other things with us in the meantime.
I asked almost the same question when I first arrived. The truth is that not everybody's okay with all of this and we don't necessarily trust what's going on around us. But we adjust, for lots of different reasons. For some people this place is better than where they come from. Others accept it because it's better for the people that they care about even if it's not ideal for them. And some just find ways to make their life meaningful here even though they really want to go back. It's better than giving up and sitting around... although in some cases, I've seen people who gave up and went home shortly after. So if you really want to go back, maybe that's how you do it.