There's multiple differences here - one is that progressive taxation is based on the idea that if you're rich, you're using the commons and the services society provides to a greater extent, thus you should contribute more.
Obviously, even with a flat tax percentage, the more you earn, the more you contribute. You make 2x, you pay twice the tax. Progressive taxation say if you make twice, you must pay more than twice the tax. If you define "rich" as the level at which progressive tax rates kick-in, that makes every American who pays taxes rich (since below certain income level you pay 0% federal income tax).
I'm certainly not going to visit any store that has electronic price tags.
So you never buy anything from the internet (by definition electronic pricing), or buy airplane tickets, concert tickets, etc?
Their idea of an offer you can't refuse is an offer... and you'd better not refuse.