I guarantee you most Firefox users either use Pocket, or don't care that it's a default feature in the product now.

I am in the boat that wishes it was removable, perhaps as some kind of "default add-on", but it's not. I'm not removing FF because of it.

And as for ads: Were they tracking people with them? Were they sending back GUIDs of my browser every time I loaded a new tab? This is a legit question that would affect my opinion on the matter. The ads I see are brief, and cannot take more than a miniscule amount of data to serve. By those metrics, I have no problem with them.