I usually find that when employers haggle over vacation days, its a huge warning sign that its not going to be a place I want to work. I usually press them for extra or make up a "previous engagement" that I'll need time off for during the bargaining just to see how they react.

Then again, I always did find all of the ceremony around "earning" vacation days through attendance, banking sick days, and rolling over vacation like its cellphone minutes to be completely insane.