Until they find out that while they were getting 3% raises and their salaries were well behind the developers who cane in after them that were paid at the market rate.
Did it ever cross your mind that there are more things than money which make a person stay at a company for a longer period?
For me personally, if the money is enough for me to make a comfortable life with my family, other things at work become important. I could never spend most of my days with assholes or do idiotic work even if the pay was way above market value, for instance. I'd also trade money for more free-time, if possible.
And yes, the company I work at does feel like a family. But nobody had to tell me this. It just does so, naturally.