I like following the traffic instructions in GTA or just walk around shoving people with drinks so they drop them. I am sure I get people watching me frustrated. In general most games where I am supposed to be abaddie, I will get a kick from trying to be a good citizen.
Then you have The Sims where you can help your sims or enslave them and torture them. I once had my sim make a pool party, but I think the game glitched because people kept swimming even when they were getting cold and tired. Death had quite a busy night, and my terrain became haunted. Hahaha.
Then you have people whooing with no playable characters like the grim reaper, a frigging scarecrow, etc.
In Jet Force Gemini, for the N64 there is a race of Koala like people you need to save from the evil invading alien ants, but you can also kill them and collect their heads. Considering they can be full families that is kind of grim.