Why are people so afraid of germs?

With the overuse of antibiotics, and stores selling a variety of “hand sanitizers” that I can’t even keep track of – this is doing more harm than good in the long run, isn’t it?
I always think back to a friend of mine who had a baby right after highschool. She insisted that everyone sanitize their hands before and after handling the baby, although he was a perfectly healthy child. I remember thinking “you are probably compromising your child’s immunity by doing this, more than someone touching him with ‘dirty’ hands.”

Is our fear of germs getting worse and, in turn, is that making things worse for us in the long run? Either by compromising our immunity or by encouraging “super-bugs?”