That grace could be perverted into license has nothing to do with grace, but with the perversion, or changing, of grace into something else. The whole letter of Galatians speaks of perverted grace, or perverted gospel (good news) … which we know is NOT grace or is NOT gospel. It has been changed, and it only APPEARS to be grace based upon those who word it as if it was.
I am amazed that you are so quickly deserting Him who called you by the grace of Christ, for a different gospel; which is really not another; only there are some who are disturbing you, and want to distort the gospel of Christ. Galatians 1:6-7
When freedom becomes just another way to bring law back into the picture for those who have been freed, then it does indeed become turned into a covering for evil. It is what Jesus told the Scribes and Pharisees. It is what James said in his letter to the same kind of people who did the same thing to the new teaching of grace that they wrongly did about the Law. And it is the same that Jude wrote of. Why would it be such a surprise to discover that people have not stopped doing the same thing they did when Jesus was here? People still pervert - change, twist - grace by making it into something else.