I've seen counterfeit coins from time to time, but today I was passed a $1 bill in my change at a Wendy's. It looked maybe a little wet or something when I got it, but when the bill taker at self-checkout in the grocery store wouldn't take it, I looked closer, and it's obviously fake. Not even a good fake. Bad Chinesium level fake.
Is there any agency investigating this stuff that would care about it for the purposes of tracking the spread? Or is one bill useless for such things?
Should I shred it, put it with my collection of apparently counterfeit coins?