One could also be upset that the female character appears to be snob and don't really care about what happens to the hero. I say that's sexist! So let's make her care about him more. No, wait, that is sexist too in a way because then the female character would willingly be like a reward... So let's replace her by a pile of money! No, then the snow man would look greedy, that's not good for kids to have a greedy hero, so why not a chocolate bar?! Not wait too much chocolate is not good for kids...

Honesly, I think only adults can be shocked by a female character who have breast. Children would find this normal. Because it is. And adults would understand the sexual "subplot" that is behind the reaction of the hero. That little short movie was perfect from the beginning. If the director wants to make changes I can understand and respect his point of view even if I don't share it but I can also understand someone who would want to make a presevation of the original. Honestly I saw that short movie back in 89 or 90 (it was the first really cool and beautiful Pixar movie with a real little story so it made an impression on me) and when I saw the new version years later I thought it looked bad.

What shocked me the most is that TV's Frink is shocked. ;)