The problem is that then you have to make sure workers feel secure about moving to work for you. So good pay, good local environment and most importantly a secure job because if they get laid off they'll have to move their whole family somewhere else.

Some companies do it (Walmart I believe) but most tech companies tend to base themselves in relatively large cities with other tech firms.

I remember a couple of years ago that people were saying Amazon had trouble hiring because even in tech-hubs they had run out of qualified people who would want to work for them.