Scream
 

In Scream, as 99.9% of you probably know, Billy Loomis, the film's main antagonist, kills loads of people in comeuppance for being abandoned by his mother, who separated from his father when he started a secret relationship with Sydney's mother.
I can kind of see why he felt murdering Sydney's mom was the right thing to do, but what was the purpose in killing all the other people who had nothing to do with his unhappiness?

The film is kind of a parody, rather tongue-in-cheek, so I wouldn't look too deep. But my best answer is, these guys are thrill seekers, and the other deaths are just to rile up the heroine.

He's getting at Sydney by killing her friends. But I could be wrong. Hey, it's a horror film. Get too deep and you'll fall out the other end.

I can't remember exactly right now. But there was a reason for killing the first girl. And a few others. They were all related or had encounters with the killers.

Stu was the one who killed the first girl (Drew Barrymore's character). She dumped him for that other football player.

Sounds about right. I remember there is a conversation in the opening where they have that liver alone joke.

Yeah. They had her boyfriend tied to a chair in her backyard.