They have left the true road and have gone down the wrong path by following the example of the prophet Balaam. He was the son of Beor and loved what he got from being a criminal.
Now they are in for real trouble. They have followed Cain's example and have made the same mistake that Balaam did by caring only for money. They have also rebelled against God, just as Korah did. Because of all this, they will be destroyed.