Originally, taxes were levied to pay for government expenses. But they underwent a malignant transformation. They began to be used to express social preferences. Tax revenues were diverted to pay for urban renewal, to encourage foreign investments through tax breaks and tax incentives, to enhance social equality by evenly redistributing income and so on. As Big Government became more derided - so were taxes perceived to be its instrument and the tide turned.
Taxes are inherently unjust.
They are enforced, using state coercion. They are an infringement of the human age old right to property. But there is no way of preventing a tax evader from enjoying tax money paid by others. Moreover, these strata of society were most likely to use tax planning to minimize their tax payments. They could afford to pay professionals to help them to pay less taxes because their income was augmented by transfers of tax money paid by the less affluent and by the less fortunate.