Well, maybe there's a deeper truth to qp11's statement:

I completely agree that moving to the tech city _du jour_ caters to the demographic of mid-20 "anywheres". Having a family, long-term friends or obligations such as elderly care rules you out. Or god forbid: A time-consuming hobby or in general something apart from work that gives meaning to your life.

And that's exactly the point! You only get those high wages when you put in the 60–80 hours a week (or 40 very focused hours a week) that you can spend if you live for your work. To the employer, such dependent, driven employees are very valuable. Much more than some family father who comes in for 20 hours a week and is often tired and just wants to get back home to play with his children.