[jzb]

“Is a farmer entitled to the entirety of your work output because you ate a vegetable grown on their farm?”

Bad analogy. I pay a farmer (directly or indirectly) for the vegetable. It’s a simple, understood, transaction. These players were generally unaware that they were gathering data for Niantic in this way.

If data is crowdsourced it should belong to the crowd.

[try_the_bass]

Niantic pays you for the data you collect, as well. It might pay you with in-game rewards, but if you accept those rewards, this is, as you put it, "a simple, understood transaction".

The farmers you buy the vegetables from are also generally unaware of how you use them, too!

I fail to see how you're differentiating the analogy from the original example.