One of the biggest appeals of CloudFlare (aside from DDoS protection) is they don’t charge absurd^[unless you’re big enough they think they can shake you down] prices for bandwidth egress. AWS, et al have honestly predatory bandwidth pricing, they could be 1/5 and still profitable.

So given the choice of paying $30 in AWS egress that could balloon to hundreds, or a flat $20/mo, it’s not hard to see why so many people choose CloudFlare.