Is this a thing?

A RF pulse strong enough to shut-down a car's shield ECU would most likely at a minimum lock-up your phone or fry your receiver module. Did you have to restart or reset your cell phone????
Something built 40-50 years ago; not to military standards; would be a big maybe. Everything built while and after cell phones was a large brick gets some kind of RF shielding.
Second question is: why would a group of really cheap, cheapskates be drinking at a bar? If they were truly that cheap, hosted in a park or backyard where the entry fee is a bottle???? See; I know some truly cheapskates too.

 

Maybe it's not something exotic that generates a high enough signal for EMP or something weird, but maybe enough to interfere with the signal from the key fob in your pocket.

There are also amplifiers that thieves use to amplify the signals from the fobs hanging by people's doors so the car thinks the fob is close enough to the door and allows the thieves to open the car door. If your "buddy" had one of those, the signal would be delayed a bit and the extra power might make it so neither one work correctly with the car's FOB inside the car detection.

If it happens again, have him step away from the car, lock the doors and try again. If it runs, leave his a$$ by the highway in the middle of nowhere.

 

If the car is running the key fob isn't in play. Toyota engineers has thought of that - if the fob battery should die while car is in operations; that would be dangerous.
That's why you don't leave your car running; anyone can jump in and drive it off. The car doesn't look for the fob again until the car is off.

 

I recall messages here a decade or so ago. Start your Prius and through the key fob out the window (or just hand it to someone). You can drive as far as you want, but don't power it off because you'll be stuck

Mike

 

The easier way to be stuck is to drive your spouse somewhere and drop her off. Your fob is back at the house but her's started the car. You drive to the club, gas station or hardware store where you shutdown and later can't restart it.