This is exactly faulty set of assumptions being challenged here.
Not everyone gets that $150K offer, and that's increasingly true the further you are from a healthy white middle-class male.
Not everyone wants to move to the Bay Area and unless you're a friendless orphan the further that move is, the more travel expenses you're taking on.
Not everyone has family who are completely self-sufficient and will never need help. (Speaking personally from the “parents have never helped with rent; have helped parents with rent” club)
Not everyone can find 5 roommates they're comfortable with, an $800 car at all much less one that runs perfectly with no maintenance costs as you're assuming. In reality, most people buy newer cars because it's better to have a fixed bill than deal with the missed work and random thousand-dollar service bills which you tend to get with $800 cars.
Not everyone's health is compatible with living on canned chili and even if you don't have any long-term issues, you'll probably want to get some basic nutrition before you develop some.
If this actually worked for you, great. All we're saying is that you should be less quick to forget that other people had it harder. I think that's especially true because when I think about the people who over-spent, they were never starting poor — they grew up comfortable and never had to worry about true disaster.