Well if someone's hosting guest posts on their blog for non-SEO purposes it's generally because the think the guest blogger's writing is good and that their regular readers would be interested in seeing it.
From what I've seen, it's more or less the norm that guest posters have a blog elsewhere that's linked to in the post; if they didn't have one the host would have no way to assess the quality of their posts, and reputable blogs don't accept guest posts from people whose blogs they're not comfortable promoting to their readers.
From what I've seen, it's more or less the norm that guest posters have a blog elsewhere that's linked to in the post; if they didn't have one the host would have no way to assess the quality of their posts, and reputable blogs don't accept guest posts from people whose blogs they're not comfortable promoting to their readers.