No facebook account here. Never had one, never will have one.

Also pay off CC in full every month, so no interest payments on what are effectively short term loans.

Neither is at all psychologically expensive. However paying off CC in full every month does require sufficient income (and/or restraint in spending for those without the sufficient income) to be able to do so.

Spending cash is a lot harder psychologically than spending money with a CC. Dopamine is in effect.

Much easier to keep scrolling and consuming on FB than stopping.

That's the comparison.

For some, it only takes discipline while you're establishing the habit, then it is very easy to keep it rolling.

I'd say FB is way different than the discipline to not over spend on CCs in a community like this. Not over spending on CCs being far easier.

It depends on what your choose to define as overspending.

Easiest thing in the world and it is psychologically a gain, not a cost.

What exactly?

Not using facebook.