I think the only way to get around this loophole is for companies that offer "unlimited vacation" to have a mandatory minimum amount of vacation, and if you lea

I think the only way to get around this loophole is for companies that offer "unlimited vacation" to have a mandatory minimum amount of vacation, and if you leave without taking the full mandatory minimum you're compensated based on those unused vacation days. For instance, if I were running/when I run a company I'd offer unlimited vacation with a two week mandatory minimum, which rolls over up to a four week mandatory minimum. So if you only use one week of vacation in year 1 and then leave, you'd be paid for a week's worth of vacation. If you stay on to year two, your new mandatory minimum is three weeks and you'd be compensated accordingly if you left without using it all.