That isn't really the way RSS is supposed to work. When you pull in syndicated content from other sites the idea of sharing the syndicated content is to link back to the source. Not doing so in most cases would be unethical content stealing and it hurts the actual author of the content because if google indexes the same content on a different site with no links back to the source it dilutes the value of the original content by sapping search results to a site that is just duplicating content.
I "could" easily implement an option in the Feed Manager to not make the title be a link and while it would not be as bad in the situation you describe if the sites are both operated by the same customer, but I don't really want to encourage unethical use and I would question whether this is really a good idea for your customer or not given that it would still be diluting the seo of the source site owned by the customer. It would be far better to not have content duplicated across sites without links.
Many feeds only include an excerpt of the content for the very reason that if they put the full article in the feed it does not encourage visiting the site of authorship and other sites may abuse their content by not linking back to or crediting the source. In that case there is not a good way to pull the article detail at all since it is not included in a feed.