Sure, but if you make a visible button on the second most popular browser that links to your product, you would get a lot of users and some of them would sign up for the paid service.
I bet the number of users would be much smaller if there was no such button.
Yeah, of course the numbers would be smaller if there was no such button, nobody is saying otherwise. They're just stating that nobody was forced to use Pocket after the integration.
How hard is that to understand?
> Force [verb]: make (someone) do something against their will.