I don't think you need to be worried about it being free. It's not actually free for everyone, I'd assume. The fact that they let you put a badge on your page

I don't think you need to be worried about it being free. It's not actually free for everyone, I'd assume. The fact that they let you put a badge on your page to get "4x more views" makes me believe they're going to price it similarly to how Mixpanel is priced—it's free up to a certain number of interactions, and then has tiered pricing from that point on.