Cloudflare has created a bit of grief with regular users getting spammed with "prove your human" requests.
For example, I do not allow reCAPTCHA.
As a similar commentor noted, when just casually browsing I don't really have any desire to try hard to read random content. Should I absolutely need to access some information garden-walled behind Cloudfare: I have another computer that uses much less restrictive black-listing.
Cloudflare's automatic checks (before you get the captcha) must be pretty close to what ad peddlers do.