The GODDAMNED cat
The cat in the movie isn't irksome for only one member of the cast (The dentist) but for the audience at the large too. Under the given circumstances and looking at the gravity of the situation which was purely life and death question, no PET must and could be allowed to be kept. As suspected by at least one of the members and again by the audience at large, it was this damn cat which led to the catastrophic end of the story.
Apart from the security and safety considerations, they should not have allowed any member with any pet due to the extreme shortage of food.
To me it seems a perfect folly to entertain or include anyone with a pet or that kind of sentimentalism, for that matter.
I would like to say that the cat and the Nazis brought death and destruction to this unfortunate household which as a whole was responsible for foolishly keeping a pet and thus inviting their own misfortune.
PS: For those who wish to ask, confirm or know: 'Yes, I hate PETS!, LOL!'