If that works for you, sure. But most would seriously weigh that trade off. With another 70k / year after taxes you could retire way earlier and do whatever you want.
Early retirement is almost always an option for middle-class or better Americans. It's just a question of how much pain you want to put up with in terms of housing, lifestyle, where you want to live, whether you want great education for your kids, etc.
I used to agree with your comment but don't anymore. I have enough money at this point to earn 10s of K/year investing in real estate or doing something else. I don't because I like working in tech, being part of a team, using my education and talents, and generally working on making the world a better place.
Seems like you already earned your nut. Those that haven't might want to take that Google tradeoff, esp. if young and unencumbered, so that can get to where you're at.
Your middle-class also seems to be a bit different than my middle-class, especially in cities where jobs are.
