They serve as a subsidy to exports, but also act like a tax on imports.

它们成了出口的补贴，但同时也成了进口的税收。

youdao

The minister said he had no plans for such expansion but that liberal arts students did act as a subsidy for the college finances.

BBC: Question Time - Employment and Learning, and Enterprise

However, it was massive government support for the housing industry through the mortgage deduction, rules such as the Community Reinvestment Act, and a multitude of subsidy programs that created the property bubble which burst so disastrously in 2008.

FORBES: Raise Taxes To Clinton-Era Levels? How About Spend At Clinton-Era Levels?