Leaving the door open

Quite apart from all the other batty things about this film, why did no-one ever close the door of the cabin? It was left wide open the whole time anyone was in there, from when the heroine goes to sleep and Jimmy Fuller sits up as sentry, to when they both go out into the woods .. in fact all the time. I found myself shouting CLOSE THE BLOODY DOOR! It was supposed to be a swamp, no doubt full of mosquitoes and other bugs, so why would you leave a door wide open at night? Why would you leave a door open at night in the middle of the woods either (bugs just as bad). I would like to know where in Canada this was made in woods with no mosquitoes, because maybe I would like to live there instead of where I do live (with loads of them).