baimun
Funkasaurus Rex
I fight this battle with my adult children as well. They assume they can always pay with card....until they can't. There have been multiple occasions where I've had to pick up the tab (e.g. ice cream, beer, etc) because the venue is cash-only.
Kids I get.... the concept of what constitutes "an emergency" is different when you're younger.
"But I was really really hungry!!".... or "they didn't know what that guitar on the wall really was at that pawn shop".