http://www.encoreopus.com/marketing/pr-tip-how-to-pitch-a-blogger.html

Although, I think they should be more concerned about poorly pitching a blogger.

Journalists are likely to just ignore a bad pitch or a pitch on a topic they don’t cover.

A blogger is likely to do a post about a bad or irrelevant pitch, and maybe even include it on their blog if it is done via email.

Of course you are absolutely right.

The one difference I find is that many people who pitch bloggers have never pitched or considered pitching a journalist.
Maybe this is because bloggers seem more approachable to many people?