Have to disagree there. Just because my blog has an RSS feed, doesn't mean you can repost the contents on another site.
As someone who has had spam sites set up based on my feeds, it's pretty friggin' annoying.
This is what syndication is for. I choose what to syndicate, to add value to my website. And you gain exposure from appearing on many different websites. That's why most publish just a teaser of each post and not the full body.
Again, I'm not arguing about what is right (or fair) and what is wrong. I'm just saying that the protocol has been developed for this use.
I like to include full feeds because it greatly improves the experience of people consuming my content.
I think we agree that stealing someone else's content and republishing it with your own ads is both legally and morally wrong. I don't see how publishing in RSS changes that.
And where does that leave services like google reader? If they decided to start using ads, in which of the two groups would you put them?
RSS readers are relatively new and will probably evolve in unpredictable ways. The distinction between what is a "feed reader" and what is a "web site" is already outdated.