Here’s an analogy.
Imagine it’s the city of Springfield and Fat Tony is the local mob boss. He runs all the organized crime in Springfield - the brothels, the casinos, the opium dens, the speakeasies, etc. And the reason he’s able to get away with all of this is because Mayor Quimby and Police Chief Wiggums are corrupt - they take Tony’s bribes and let him do whatever he wants. And most of the other politicians and police officers are in on it as well.
Now we’d both agree that the corrupt government in Springfield is a problem. But the libertarian solution is to essentially abolish the government. That would remove Quimby and Wiggums and the other corrupt officials. But it would leave Fat Tony untouched. If a corrupt government had “granted” him the power to run his crime empire, a non-existent government would make it possible for him to run an even bigger crime empire without worrying about the government.
Now you can argue that all of the things Fat Tony does are still illegal. And that’s true. But the laws alone don’t stop Fat Tony. You have to have somebody that has the power to enforce those laws.
Fat Tony doesn’t need a government to allow him to commit crimes - he does that on his own initiative. But the city needs a government to stop Fat Tony from committing crimes.