I can't understand that kind of thinking. Never felt that way (it's also not how relationships pan out in general from where I come from...I'm always shocked about US people moving in with girlfriends / boyfriends after 1-2 months).
I mean just think about the enormous loss of freedom (months spent bickering) and money (moving in, moving out, finding an apartment, living in a hotel for a while, bla bla) that a failed relationship can cause. Plus all the psychological stress. Much better to wait some, perhaps do some stupid stuff together (like a trip somewhere exotic) but still each one has to have his own life.