And I can't blame the companies for making that decision either, why should the company serve your app if they're not even getting any traffic from it? Which would be a logical argument, except these companies open up their APIs and act like they are ok with it at first, and developers spend time building on top of them, creating even more useful services, making the original company even more popular, and then after those companies benefit from these developers, they shut them down.
This is similar to what happened in this case, which I think was a complete dick move by Soundcloud: https://medium.com/@padschneider/r-i-p-soundflake-79f7cf5f9d...