But it should seem pretty obvious that something like maternity leave couldn't, and shouldn't, be an "earned benefit" - should everyone except to accrue a month of "maternity leave benefit" through the ages of 20 and 40 or something?
It's good that we do have benefits that only apply to subclasses of people (i.e. parents), but how those benefits are structured shouldn't be at the whims of a company if we feel, as a society, that they're important for people generally.