“They don’t count their income as income ....”
Sounds like you are only making an argument in favor of ALL federal taxation being consumption based. If so, then I agree.
The income tax was invented to tax the rich. A bad and immoral plan from the beginning. Then eventually congress spent enough that you and me necessarily now are considered “the rich.”
I don’t think you can apply a consumption tax large enough to meet our revenue needs without making it impossible for people in lowere income brackets to survive.