I vaguely recall this happening as a joke in some form of media but all I’m getting are statistics about currency being contaminated with cocaine when searching for it online.
Edit: My dad wants to buy scuba equipment but doesn’t know where to buy it or what size he is for a lot of it so I was going to write “For scuba equipment not for drugs” on one of the bills as a joke for his Christmas present.
Searching online points to the movie Drillbit Taylor maybe being where this came from, but I have not seen it to confirm.
I think that might be it! I definitely saw that movie a few years ago.
Nice detective work