I believe that G look at it as a + to the feed source (in this case Your site). It's not considered as duplicated content (I know we can argue about it
) or stuff like that but as popularity of Your content (something like backup links). If it wasn't like that all sponsor feeds would be fucked up and looking at few of my blogs that uses only RSS from sponsors for almost a year now they'd be fucked too. Instead traffic numbers go up.