In my childhood, we drove everywhere - vacations, moving cross country to escape death threats, traveling to visit distant relatives, moving back cross country after my father died.
And the one constant was the road trip cooler. Stuffed with soda, snacks, bread, and lunch meat, that thing got toppedd up with ice at every hotel.
And as an adult, I don’t really do that sort of travel anymore, but as others have said - for chilling drinks and what-not. (But never for putting into drinks.)
Oh, no worries. As a kid, it was a real adventure! I didn’t really learn about the reasons behind it until a few years later. And at that point the risk of danger had passed.
(Although, I probably shouldn’t have been told about it until I was an adult.)