I'm not sure it takes an efficient market for candidates to be able to do a simple math problem. The company that offers 4 weeks vacation a year pays a $90k salaried employee the equivalent of $51.10/hr; the company that offers 6 weeks vacation pays $53.50/hr, or 5% more.

Comp clearly isn't the only reason people pick jobs, but it's a big reason.

There's a "quality of vacation" point you're making, but generally I think the real issue there is that employees are pushovers, and ask permission to use all their vacation time all at once, instead of just informing their employer that they're going to take July off.