Gotta say I agree with Zara and Kim. I teach in a middle school, and the hugs that I witness have nothing to do with saying "hello". More like "Hey baby... you wanna come back to my place later?"

School is for learning. You can be social and hug all you want outside of school. While I don't think it's horrible to do in school, it just gets carried away, and then you get making out in the hallways and kids cutting classes or being late for class. It's not keeping focused on what they are in school for. Education.