Vegeta killed a stadium of innocent people to force Goku to fight him.
He gets rewarded by the namek dragon when dende used the following wish " i wish all the people who were killed since the wizard babidi arrived on Earth except the most evil ones." Vegeta gets revived even though earlier that specific he had just killed a bunch innocent people.
And yet, slopovich and yamu we're not revived and they were actually being mind controlled.
Majin Buu beat the piss out of him, then he EXPLODED to try and take Buu out. Then right before he did that, Piccolo basically told him "You've been an evil dick all your life. No you won't get to see Goku."
Then he came back and fought Kid Buu and was beaten even worse. Anime is full of karma houdinis...Vegeta isn't one of them.