In theory it is not very complicated for a H1B to change employer. It simply requires the employer to file a petition to sponsor the H1B. It doesn't count towards the "seats" available yearly, and it's almost guaranteed to be granted. There is a small cost, maybe a few grands. If you think about it, it's way cheaper than paying recruiter fee fo example.
In practice you're right though. Most companies have limited experience with this process and just don't want to get into it.
In practice you're right though. Most companies have limited experience with this process and just don't want to get into it.