My University had two snow days my Sophomore year....but none since then. The first time they had a snow day was half way through the day they decided to close the University. I was already done with classes so it wasn't any big thing for me.
There have been other times when I was surprised that the University held classes. A few weeks back we had negative temps and a terrible wind chill and they still had classes. It was horrid walking across campus and they really should have called off classes.
However, I will say this much...some teachers have their own rule that if all the metro area public schools close they won't have classes. So it's purely up to the teacher but technically they're not supposed to cancel!