It defeats the point of finals week to have finals during the week before. I think it's a big problem on campus. This practice is in violation of university policy, and while some departments strictly enforce it, others do not. The provost office is responsible for regulating it. Some students, however, like having finals early.
Many professors offer an earlier final as an option to students.
It's really convenient actually. Our professor made it an option for us. This way, I can get one of my finals out of the way before studying for the rest. Review sessions could be another possible stress-reliever for students. Some professors offer a review during class, others offer one outside of class, and some offer none at all.