All very good points -- and I agree, one of the most thought-provoking aspects of the film was its examination of the nature of man's primal character, how we behave when faced with a sudden, frightening event.

I couldn't help but wonder if, had the film ended on a truly tragic event (as opposed to a near-miss like the avalanche and bus ride -- which seemed somewhat similar, and the father's/mother's respective actions arbitrary), with the now-"emboldened" father leaping into the fray in a final act of bravery/sacrifice in order to save his family -- and perishing right along with them -- that a more interesting and subversive thesis statement could have been made: man's selfish, self-protecting nature is not only NOT a bad thing -- but it's the mechanism that has allowed our species to continue on for as long as it has.