This is the free rider problem. Free riders are people who benefit without paying.

这是搭便车的问题。免费的乘客是那些不用付钱就能受益的人。

In the past, Trump has called Japan and South Korea " free riders."

特朗普曾称日本和韩国“搭顺风车”。

Unions counter they face a “free rider” problem whereby non-affiliated workers receive the benefits of union negotiations without contributing financially.

工会反驳道，他们面临着“无本获利”的难题，在这样的背景下，非直属工会的员工，就可以从工会谈判获取利益，而不掏一分钱。