That's pretty interesting. In fact, this means Steemit could be abused by using it as an image host without actually ever using the service. It would actually be quite easy to automate too.

Note: I'm definitely not saying people should do this (it's pretty bad for the community to use the site's bandwidth/storage without giving back by posting content). It would be possible though, which means eventually someone will do it (Murphy's law). I wonder how Steem could protect itself from this?