Honestly, after many years in the newspaper industry, you learn a few things. One of them is that many publishers are not technologically savvy. They've done it themselves for years, and aren't interested in paying an outside group a cut.

Simply put, its not intuitive to them. It's a much different business model than they have operated under. It takes time to understand, and many aren't willing to put in the time. Its also at times proven to not be as good as the claims say. There have been exchanges that promise big value and just end up serving cheap house ads that detract from the site and don't pay enough to make the accounting worthwhile.

Case studies are one thing, but get in front of publishers at the conferences and events. They like to here successes from other publishers, not sales people. Use your current clients to leverage new accounts.