You don’t need to mention that you are in the top 50% to make your augment stronger. You should probably even actively avoid saying it so that people don’t think you’re relying on selfless reasons, (hey everyone I’m the nice one in the room) to further your point, because others may not feel that way about themselves.l, at least not to random strangers in the bottom 10%.
Anyway, making more money is just a measure of one’s ability more or less (not a causation but a strong correlation). Therefore to the extent that one works harder or provides more value to others and is rewarded for it by increased earning power, they should not be punished for it by an arbitrary tax on their transportation needs.
I think it might make sense to create countries or places where people in the bottom 10% live with minimal conveniences, a place like Thailand when everything is cheap.
In additional to above requiring everyone to pay the same amount creates equality and most likely moves technological innovation ahead that much faster because everyone feels like they are getting value for their money and more likely to spend even more on improvements.