People vastly underestimate the "peace of mind" costs - once those are taken into effect it can suddenly make sense to do things that many consider "financially unwise", such as having a large emergency fund, paying off a mortgage, etc.

And once you do that you can find yourself suddenly feeling much more free - knowing that even if everything goes south room and board is taken care of can give you the courage to take risks you'd not otherwise take, such as starting a business, a family, even moving.

The main thing about "living paycheck to paycheck" that scares me is that feeling of being trapped.