About kicking dogs... I found that the only time I could kick a dog was when it attacked you first. Otherwise you can't. I think Rockstar was being very careful - no cruelty unless provoked.
The game's careful in other ways. The panty raid mission was for the benefit of a TEACHER, not a kid. So it's the adults who are pervy, not the innocent kiddies who do their bidding.
Doesn't explain killing poor little rats, though.