tedster - 9:19 pm on Sep 28, 2011 (gmt 0)
How many words are in the feed's description for the average item, and how many total words in the average page's content area? It seems unlikely that your situation is a duplicate content "penalty" (or really, a thin content penalty) if there is a significant amount of unique text on each page.
However, if many other sites are offering the same items from the same provider, then your site needs to offer something quite unique and compelling compared to the competition - at least if you hope to be one of the results Google would offer for the main product keywords.
You can't do well in search traffic today if you are "just another website offering the same list of products" that many others also offer.