US does have marginal tax brackets. There is the benefit cliff. But there are also tax credits that phase out progressively with higher incomes. Though I dou

US does have marginal tax brackets. There is the benefit cliff. But there are also tax credits that phase out progressively with higher incomes. Though I doubt, but don't know, than any of those produce net negatives. They may be closer to net neutral. The OP was describing the same thing as you. People don't understand marginal tax brackets and do silly things like not want raises for tax reasons.