Why do we pinch someone not wearing green on St. Patrick's Day?

I found the answer to this question online. I thought I would share:

It's thought that the pinching started in the early 1700's, about the time that awareness of St. Patrick's Day as a holiday came to the fore, too, in Boston, in the Massachusettes colony. They thought if you wore green it made you invisible to the Leprechauns, which was good because they would pinch anyone they could see. So the pinching is to warn and remind you of the Leprechauns. Pinching those not wearing green on St. Patrick's Day is an American tradition, having really nothing to do with Ireland or St. Patrick. The truth is, the Irish think that Americans are crazy. St. Patrick's Day is not even remotely celebrated over there as heavily as it is in the U.S.

So, there you have it. We're just a bunch of crazy Americans going around and pinching people on St. Patrick's Day. I'm ok with that. It's still fun! I actually forgot that it was St. Patrick's Day this morning, but I just so happened to pick out a green shirt to wear! Little did I know I was dressed for the occasion.

Happy St. Patrick's Day!