Using a Press Release distribution service can be a smart decision for some companies. But, why are you crediting them in your press releases on your own website? Some of these services even go so far as to include a link to themselves in the header of the press release. Even worse, they place a copyright for themselves at the bottom of the press release when they had nothing to do with writing it.
The bottom line is that you are paying them, not the other way around. So you shouldn’t be giving them free advertising. And unless they wrote the content, they shouldn’t be getting a copyright on your content. Even if they did write it, PR firms never place a copyright for themselves on anything they write for a client. So, why should the Press Distribution service get it.
Keep in mind that the more we see copyright claims on content, the less likely we are to publish it. That is even the case with press releases.