I actually once read something like financial companies prefer to promote people with family, house etc instead of single guys because that's the way you lock them down. If they cannot afford to quit the job you basically own them and you can exploit however you want.

I think in a similar fashion to the writer but have a different approach. By learning to live with very little and be happy with the minimum, I'm not afraid of having to leave a place and give up a nice salary. Having the money is a nice plus and I can enjoy buying stuff and nice restaurants, but I don't make it part of who I am or the foundation of my happiness. Or at least I try ;)