Why are some people so frugal, even if some are wealthy?

Because being frugal is often how they GOT money. They learned to only spend as needed, to invest smartly, to stow away money. Obviously they have some spending money, but often the whole way that GOT into a better position that us was by saving when possible and being money smart. Thats why so many rich people have that mindset and so few NOT super rich people dont get it- that mindset can lead to wealth, and if you aren't wealthy, its easy to not understand. Thats how they got more money in the first place, so I find it silly to look at people doing better than us and criticize them. They are doing better than we are, and I have no room to criticize how they act with their money when clearly they are more money smart than most.

Unless you have discord a gap in a business you can exploit and capitalize on, find a loophole to exploit, win big on a bet via stocks and trade or just be lucky and inherite enough from already rich family or win the lottery l. The odds of you getting upperclass rich is very, very low.

Majority of people need to spend money to survive and can't afford to save or spend it on things that may or may not pay out. And the rich usually dislike spending money cus that's how the got it in the first place. Spending little and saving lots.