It may not seem like it to those of us who know how to do it, but there actually is quite a barrier to entry. You or an organization needs to have the skills to utilize machine learning algorithms, test them thoroughly, package it in an easy-to-use application, then market it and compete against competitors. Just ask your every day Joe what you should do with a learning rate if your error rate suddenly spikes or how to monitor for overfitting. Then ask them how to form an LLC or how to create and audit a liability release waiver for clients.
I also think part of the "real skill" in this sort of business is making sure you have someone around when it breaks. If the pearl counting algo goes haywire, the pearl company wants to know that they'll have someone to contact to fix it.
The barrier to entry is that many niche markets that latch on to the original service over time are incredibly random and difficult to associate with a uniform market. You can build and price a cheaper app, but reaching the set of customers would be difficult.
I imagine it's all in the business development. I for one never would have thought to reach out to pearl traders to service their counting needs, and odds are they're not actively seeking out computer vision expertise.