Why so many Americans fail to save money and/or go broke?

My boyfriend and I are Americans. We're in our early 20's. He works a career and currently makes around 40k as an assistant manager, is not on any public assistance, owns a house, car, and after mortgage, bills, food, etc he still manages to save 1/3 of his salary (between 10-15k).
I'm a college student who technically got a full ride in college all because I spent months before starting (and weeks between semesters) applying for over 100 scholarships online and through mail, and proofreading/editing my essays then was awarded multiple scholarships so now I won't need to take out any student loans during college.
Point being, there's still a lot of Americans out there who make more than he does yet still end up broke or fail to save money. And there's students who complain about being in student loan debt when there are so many scholarships available (local and non-local). Why do people make it so hard on themselves?

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