This again? Well, let’s view this as a teaching moment. I draw your eye to this:
“Unfit to be reissued” means that it wouldn’t be accepted as “money” by someone. And “with intent” means you seriously have to want to make it unfit to be accepted as “money”. Scribbling on a bill, putting stickers on it, as long as it’s recognizable as a bill and has its serial numbers intact, it’s fine, and the Money Police aren’t going to spring out from behind the register at McDonald’s if you spend it.