Earlier quoted context omitted.
> The hidden cost, of course, is that the NSA learns everything there is to know about you and your customers. That depends heavily on the kind of site you're hosting there. I have a small site on Cloudflare that lists a brief introduction of a sawmill, its operating hours and contacts, and a map that advises which roads to take to reach it. Everything's public already. There's some very modest value in tracking who…
Do you really need Cloudflare for something like this?
And I'm satisfied with Cloudflare's explanation to the free hosting: the more sites are on Cloudflare, the more are ISPs interested in having good connections to Cloudflare. Makes sense.