I investigated Cloudflare and the $200/mo plan seemed to good to be true so I contacted sales who verified that yes, it was too good to be true and my usage of the $200/mo plan would violate their ToS. They initially quoted $5k/mo over the phone, and then came back with a formal quote with a number much higher than that.
My take is that Cloudflare's product is so good that they can get away with any kind of sales practices they want. It's like shooting fish in a barrel: just analyze customers on the $200/mo tier and find the ones that look like they could spend way more. It's not even wrong in concept: sales upselling is SOP, and the low-cost tiers provide a lot of value to people who couldn't otherwise afford what they're offering. But the combination of the two sure leaves a bad taste in my mouth.
AWS doesn't have transparent pricing either, but in a different way. Yes, you can use more and more bandwidth and know exactly what you'll get charged, but once you get to Cloudflare Enterprise levels of bandwidth the AWS sticker prices would be astronomical and everyone negotiates non-transparent lower rates.