I don't have any great immediate answers for you. JFBConnect sets up Open Graph tags, includes the AppId in the Javascript initialization, adds the proper namespaces to the HTML document and various other things. We take great pains to ensure we follow all of Facebook's recommendations for post attribution and app configuration.
There's no reason that JFBConnect should be interfering with or reducing your overall reach. If nothing else, everything we do should improve that reach.
If there's a specific reason you think that JFBConnect is the cause of reduced reach, please let me know what it is. Looking at your home page, everything there seems setup properly. I do see that you're using jReviews and AddThis, and likely other extensions that integrate with Facebook. jReviews specifically looks to be adding the followig into the HTML:
jreviews.fb={"appid":"","og":true,"xfbml":false,"optout":false,"post":false};
I don't know if that code is ever being called, but it looks like they're setting up something with Facebook without supplying an AppId. In general, we recommend that other extensions shouldn't try to intialize the Facebook library at all. I don't think this is really the cause because, even if jReviews is re-initializing the Facebook library and even if they aren't supplying an AppId, it shouldn't prevent Facebook from surfacing your posts.. but then again, I can't guarantee that.. or perhaps the attribution / stats are missing because the AppId isn't included. I really don't know.
Again, any details on the differences between this site and your other site (all extensions used, features configured, etc) may help. However, I really don't know if there's much we can help with. It may be something you need to contact Facebook about for assistance.
Thanks,
Alex