Ah that's a fun misuse of USB ports. The companies will often even dodge issues with the USB-IF by labeling the ports as Type C and letting the customer's mind fill in the word USB.

I wish these devices would just use barrel jacks, labeled with the voltage and polarity. But these manufacturers know that the USB-C port weighs into buying decisions (and they know that most people have zero clue about the difference between a physical port and the electrical/protocol specs).