Gruber killed people because it made his robbery more convenient. He shoots the corporate dipshit guy in the head just to emphasize that he is serious. How much more villainous can you get?

Don't judge.

Really? Gruber was an out and out thief and murderer who used terrorism as a front for his plans.

The Sheriff was also a proper villain, doing whatever he could to try and ensure he ended up on the throne.

I concede on Snape.

But if everyone has just given what Gruber wanted no one would have gotten hurt. They open the safe, move out with the money and everyone but Bruce Willis' career is happy.

Agreed for Snape's character.