Yes, that's precisely the same behaviour as I see from my 2012 Golf (same VW CAN-BUS architecture) when it has a flat battery.
Your best option is to find someone in the car park with jump leads and get a jump from them. If the car has a manual gearbox you potentially have the option of bump / roll starting it. Other than that it's a case of either charge the battery (possible if you have a solar charger and an hour or two spare), use a "jump pack", replace the battery with a charged one or remove the battery, take it somewhere to charge it and return with it charged.
However I assume that time is a factor and leaving the car potentially unlocked doesn't appeal either. Jump leads would be my number 1 option.
Of course if you are a member of a motoring organisation which provides a breakdown service, you could call them out.