I agree, so many people spend so much time saving money, what if they spent that time building a business or educating themselves? There's a hard limit on frugality, but there is no such limit on building wealth.
Frugality is a force multiplier for building businesses. I bootstrapped for quite a while before going full time. If I had more expensive "lifestyle" needs like a car (and loan payments), an apartment in a more exclusive neighborhood, fancy clothes, or what have you, I'd still be building someone else's business rather than building mine.