It's the same at my school. No kissing, nothing but hugging, hand holding, you know. But they do it anyway, all the time, in the middle of the hall, etc.
I don't find anything wrong with it, as long as it doesn't go... further, because that's not meant for public, especially a school.
I just turn my head away and don't watch, because you're really not supposed to watch that, it's like a private moment between two people, and I don't want to intrude on that.