There are people who believe that if you can't sell the surfer on the index, you aren't going to sell them on the main or gallery pages either.
The index serves multiple purposes. It's a warning of sorts, your first attempt at the sale, and a traffic trade. If traffic isn't sent past the recips you could bet that traffic would suffer. Each recip produces very few hits per site, if any, but over thousands of sites, traffic builds. Take those recips away and stop that flow of traffic from list to list and you'll see the amount of traffic being sent to your sites drop off. So, what I am trying to convince you is, in the big picture, recips are good for both list owner and the submitter. Cherish the reciprocal link.
Don't treat it like a traffic leak.