How common of a bit is the "throwing batteries in the ocean" outside of hexbear?

I just heard someone say out loud, when joking about red flags and green flags in relationships, "My green flag is people that throw batteries in the ocean". And I'm sitting here with my internal monologue screaming at me "AM I BEING DOGWHISTLED HERE? Have I actually discovered a wild hexbear in the wild in the most absurd way? No way!"

Ergo, me here asking if it's a common bit or a hexbear special. if it's the latter, i have a message for the person that said it out loud should you be reading this: I hate you so much