Yes it absolutely does. Even after a progressive tax you still hold disproportionate wealth to your tax bracket if you are an upper class individual. If everyone paid a flat tax, most of the wealth held by society would be in the pocketbook of the elite and not the general public. Even after a 20% tax on a 200,000 income you still have more than enough wealth to live a very comfortable lifestyle. After say, that same 20% tax on a poor person, he or she might not have the means to live a healthy life or continue paying for her house.