I majored in CS at Berkeley, and there were only one or two professors that I can recall who strayed even slightly from these departmental guidelines. For me, the harsh curves essentially ruined what would have been an amazing educational experience. It was basically a perpetual preparation for the next exam, because you were always competing for your spot on the grade scale.
This is a very real deterrent for not only students who need a decent GPA (e.g. for grad school), but also for those who want to actually enjoy their time at university.
[0] http://www.eecs.berkeley.edu/Policies/ugrad.grading.shtml