That actually happened to me on a very early dinner date (Ralph & Kacoo's, local seafood restaurant). I was 16, had started a job but didn't have my drivers license yet so I wasn't in the habit of always carrying my wallet (also before I had any credit or ATM card). The solution was to excuse myself to the restroom, make an emergency call to my mom to meet me in the parking lot in half an hour and give me some cash. At least a 20 min. drive, she was thrilled. I still get picked on about it today.