Been there - done it all more than once. The last one I was at the Go Karts 200Km away, had a shoot on the next night, pulled the batteries out of the camera to recharge grabbed the bag with chargers and spare batteries, No batteries or chargers, had left them plugged in at the track canteen. Had genuine charger at home but batteries in camera were the older non chipped ones that you cant recharge with genuine charger Luckily I had the original battery in the bag and was able to use that. As it was only a few dollars for another ebay charger I ordered one to get me by until the next meeting.
Cheers
Keith.