Dead battery

[Kaptkremmin]

Ok, I left the car for a fortnight with out starting and we've had a few really frosty lately days so went to it yesterday and the car wouldn't open, took the key out of the fob and opened the door, foot on the brake and nothing. Not sure if it's the original Battery, but the AA is on the way, he might tell me. I could start this myself but hey why its under warranty still, but I have a question what won't help, I have noticed every time I walk past the car, the interior light comes on,(obviously the key is in my pocket) I only noticed this when walking past it in the dark, now I always carry my keys in my pocket but is this normal and is it something that can be changed. I know someone is going to come back and say leave the car keys in the house or don't walk past the car which but be difficult where it's parked and inconvenient.

[NemesisUK]