It is also pretty rare for some code to be that valuable. It would be about as much work for to figure out hot to leverage stolen code for profit as to just write your own. Data getting stolen on the other hand is much worse.
Would you need to notify the ICO (UK) of a data breach if your code was leaked online?
Other than that I can't really think of use cases either for the code bases I've worked on.
Yes that's about it really, there's so much custom code related to our business that even if you are a direct competitor you are not going to get anything out of it.