Much of the time communication isn’t about being creative or coming off smart. It’s about effectively conveying meaning with the tools you have. Sometimes that means simple, crude language is more effective at conveying something than all the wit in the world.
So when I’m in a situation that calls for its use, I don’t care that “fuck off” is a dime-a-dozen phrase that doesn’t make sense. It’s never misunderstood, it’s cathartic to say, and I don’t need to think on the spot to figure out something more eloquent - my mind is on, y’know, who or what needs to fuck off instead.