It's grounds for a lawsuit, as I'm fairly sure it violates labor laws. Find the relevant statutes, print them out, highlight them, and watch HR squirm.
Probably not. It's been a few years since I took the in-house Employment Law class, but in the US I do not believe that you must be offered vacation time. I remember that you have to have to be able to take at least one morning and one afternoon break, but that's it as far as the law goes.