Why the fuck do people have to insist on complicating things?Maybe it is the case that S3 is the simplest thing that could work. But I think there is something between S3 and the full-blown web hosting provider he's fearing.
The simple way S3 works is as an associative memory between keys and values. As long as you know which key to use, this is a great service. But what if you need to retrieve your data based on some contents?
The key / value pair approach of S3 is the degenerate case of associative memory. I don't think S3 has to be about anything more than storage, but there I think there will be some room for associative retrieval of some complexity beyond simple keys.
If the pipe was big enough then there would be no trouble bringing gigabytes over the pipe and doing the associative lookup remotely. Or one could store in S3 the data itself under one key and various indexes under another set of keys. That's clunky but I can imagine someone trying it.
mdavidx5's point is well taken though. Keep it simple.