> In my opinion, fairness requires having skin in the game.
Everyone has skin in the game, it's called 'life'.
> Contributing proportionally would give them skin in the game
They do contribute proportionally, they have very little so that contribution is low. In general this is done because if you take the same proportion from the worst off as you do from the richest, the poor starve.
> they would all of a sudden discover the importance of demanding fiscal responsibility from those that are governing.
While they starve because of the new tax regime. I imagine the first thing they'll demand is that their taxes get lowered so that they can live, so back to square one. If there aren't just food riots first. Also it looks like you're mooting introducing some sort of unbreakable, unchangeable law so that people would demand other changes. I'm not sure that's how democracy works...
> you shouldn't tax what you want to see more of in society
You don't want commerce?
You realise that to support your scheme, sales tax would have to go up to the region of 100%?