I also deploy to S3 largely for operational reasons — it costs nothing unless it's getting pretty significant traffic, and it easily scales up to handle ~infini

I also deploy to S3 largely for operational reasons — it costs nothing unless it's getting pretty significant traffic, and it easily scales up to handle ~infinite volume in case I'm not (unlike say running on Digital Ocean or something). Another very nice piece of the puzzle is TLS certificate management using Amazon's ACM. It's no cheaper than Let's Encrypt, but it's a lot more convenient. You put it in place once, and you never have to touch it again — Amazon's engineers will deal with hiccups and bugs instead of you. It's no more convenient than CloudFlare, but I like to minimize the number of services my dependency graph.