There's no greater copyright issue than someone embedding a youtube or copying an article. RSS feeds are there to promote content and get people to visit, if someone uses a feed they don't own, they're promoting that site.
The BBC actively encourages people to embed their feeds.
I'd have a problem claiming/proving all my sites are mine, I'd put my author feed up for the blogs I write for, they're owned by others. I'd probably even want to combine some of them using something like Pipes, and there's no way that could be claimed in any way; some of my sites would need to be piped or fed through Feedburner first anyway.
Re: Including RSS feeds as sidebar modules
The BBC actively encourages people to embed their feeds.
I'd have a problem claiming/proving all my sites are mine, I'd put my author feed up for the blogs I write for, they're owned by others. I'd probably even want to combine some of them using something like Pipes, and there's no way that could be claimed in any way; some of my sites would need to be piped or fed through Feedburner first anyway.