Ah, but I would guess those are low quality users, i.e. they don't vote, they don't comment, they don't post. While that doesn't matter to advertisers, it does matter to the health of your content network. And their features have had zero positive effects on their community health.

You can run an ad on a subway and get more users. That doesn't mean you're doing a good job. The only reason those users have something to see is because of community health.