Who else think johnny didn't deserve what max does to him at the end? Ok, Johnny raped a girl earlier in the movie and set Goose on fire, but he wasn't present when they murdered Jessie and Sprog. Max's actions aren't justified. Would you honestly kill johnny rather than simply arresting him?
"I want you to want to save my life ..." Benjamin Linus
"Don't do the crime if you can't do the time"
shareJohnny played a role in the actions that resulted in the murder of Max's family. If you kill a mans wife and child (or even take part) you should not expect him to show you any mercy.
sharePeer pressure is a real thing. Someone been goaded into doing something they don't really want to do by their friends/gang like committing a crime. Johnny Boy's a drug user who desperately wants to impress Toecutter and you can see he had a conscious when it came to burning Goose and didn't want to do it.
However, I've got zero sympathy for him. Whether you're goaded and pressured or not, you've still done the crime. It's the same as the bollocks where people who have actually committed the crime plead guilty to it in court and get a lighter sentence. Why? They've still done it, I don't care that they've admitted it.
Also, even though he didn't want to burn Goose, it doesn't change the fact that he caused Goose to crash which could've killed him anyway, he took part in the assault on the couple, and was acting like a cocky little shit in front of the cops when he got off. So I always watch the climax with a big smile on my face when he's there begging for his life and crying just before he blows up. I even like to think that he did start hacking away at his ankle before he died.
But even if you don't think Max was justified in what he did, it doesn't matter because it's not supposed to be a triumphant ending for him. Max has still lost his family and best friend, and he's become the very thing he told Fifi he was scared of becoming. It's the reason why Toecutter dying last wouldn't have been as powerful because it would've felt a bit more upbeat. By Johnny Boy dying last, when Max didn't need to kill him (again I think he fully deserved it), Max has become Judge, jury and executioner and you're left thinking has he become so broken and unhinged that he'll he now just kill any criminal he comes across? Someone stealing a car or mugging someone? Or even speeding? It's a typically downbeat 70's ending and all the more effective for it.