This report is perhaps based on a false premise. While it may be true that 5% of all the users are using 50% of the bandwidth, that's only because the rest of us aren't as demanding. Were we so demanding, TCP, which is what most of the world runs on, would provide more of a fair share. It wouldn't be perfect, mind you, but particularly with WFQ, if you're using more there is a larger chance that your traffic will drop. This doesn't hold true with UDP-based applications that are less friendly to the network.
Also, where is that 50% measured? Is it on peering points or is it at the access point? If it's at the access point then (A) it could be p2p traffic that never transits a backbone and (B) some of that traffic could be dealt with by making arrangements with content providers like Akamai to bring the content closer.