Rooting and jailbreaking also gives you a couple of other freedoms that some people need.
Like testing and debugging an app that does not exist in any of the official places like the google play store, because it only exists on your laptop, because you just wrote it.
Or like replacing the operating system with a different one, which could be just a newer version of the same operating system, which no longer supports your phone, not because the hardware is too weak, just to force you to buy a new smartphone if you want certain new apps.
Or if you want to play flappy bird, which got removed from all the official app stores, and you do not want to buy an old phone that still has it installed on ebay.
If you rooted your phone and completely destroyed and removed the original operating system to install a different operating system, it cannot be undone.
They will lose players who never hacked or cheated in pokemon go if they are too strict about this. It would also hit a lot of android or ios developers who not only may have no use for a smartphone that is not rooted, but who are also opinion leaders and experts in the area of apps or software for smartphones.
For some people, rooting a phone is a necessary step in order to truly own the hardware they purchased, opting out of the hardware + OS bundle that others are stuck with. Some big brands that produce smartphones explicitly allow and support this, these phones come with a built-in function that allows you to easily root them.
