Anyone who has risen through social classes knows that poorer people use their money much more wisely than richer people :)

I don't think you're wrong, but I know people who grew up poor and blow money on stupid shit -- or at least unnecessary purchases (eg, upgrading to every single new iPhone).

OTOH, I grew up upper-middle class, my dad being quite frugal and a big DIYer. Similarly, I make good money and am also very frugal. I have no reason to flaunt money around my peers.

Exactly, it indicates profoundly inefficient dynamics. That money could be put to use far more productively.

yeah but what is value? Why someone should be worried about 20$ if he for example can't sleep and it's most important thing to him.