The Weelsmith Movie

The weelsmith movie is very true to the first half of the novel, where it presents a lone guy who's completely alone. The ending where they are clearly depicted as bloodthirsty monsters, and he just blows them all up doesn't capture the essence of iam legend. They did film the original book ending, or something approximating it, but they didn't release it. Why didn't they actually say on the d v d that they thought an explosive self sacrifice was more hollywood and would give them a better chance of success? I'm not joking with me.