My field in electronics is a great example. 50 years ago, you got with a company out of college and mostly stayed with it, pensions and all that. Now, employers encourage turnover. Companies pay more for new hires, they don't match market rates for long-time employees. There are few career growth options internally, whereas in the past you had an identifiable path upwards within the organization. Plus market disruptions can happen faster now with rapid technology changes, adding volatility to business. In my career, I've had no choice but to chase where the contract money goes.
If you are having to move for a new job anyway, and that means a raise, why wouldn't you be looking for a step up in home/neighborhood quality?