I've heard similar stories over the years.
Here's a bit of historical trivia involving 2 dollar bills. Not sure if it's true but it sounds like something that just might be.
During the run-up to WWII, in many parts of the country military training bases were opened (my father helped build one named Camp Beauregard, outside of Shreveport, LA, in 1940 while he was serving in the Michigan National Guard) as the United States started to train mostly Army troops at these new bases. Well, as you can imagine, the local town fathers were not always too keen on the idea of these young men from other parts of the country suddenly being dropped just outside their towns. Ostensibly they said they were concerned about the welfare of the young women in their communities. To overcome these attitudes, the Army decided to start paying the trainees with 2 dollar bills. When the shop keepers and business owners suddenly saw their cash register drawers filling up with 2 dollar bills, they became immediately aware of the positive economic impact that these Army camps were having on the local economy and before long, all of their concerns were suddenly seen as unimportant. The power of greed wins the day again.
BTW, I've got an uncut half-sheet of 2 dollar bills, that I bought at the Mint's printing office on one of my visits to Washington, DC, and I had it framed and it hangs in my den at home. Note that I collect both coins and currency, and have since I was about 10 years old.