> Reminds me of the time a former employer which shall remain nameless paid a Senior Developer to spend an entire year coding something a $15,000 license from the maintainers of the original library would have given them. So lets spend 6 figures to save 15 grand or whatever.

You argumentation assumes that the goal was saving money.

On the other hand, if the company's goal is to become a little bit more independent of this library (and their licensing fees), this approach often makes a lot of sense.