The other day someone complained that they found a stray hair of an unknown donor in place where it shouldn't be (I think it was in the sink of the washroom at work or something). They were a little grossed out.

That got me thinking that people over react to the sign of a hair on a counter, or desk, or yes - even in their food. I mean, think of it really: It's hair! You're covered in it. When you talk to someone they have thousands of these things in very close proximity to you. You may even know someone well enough to touch their hair, or run your fingers through it.
You may go to salons or hair stylist that use brushes and scissors that have touched other peoples hair.

It appears that when they are in large groups there's no problem. Some may even say they're beautiful. But... take out one (just one) and leave it lying around, it becomes the most disgusting thing that nobody wants to touch.

I guess it's the fear of not knowing the donor, but again, I'm sure most hair from most people is harmless.