Notice I said wide receivers as well as running backs. Teams like the Falcons and Saints spend more on offense than they do on defense by a wide margin. Their defenses are mediocre because of this more so than rule changes.This statement shows your lack of knowledge about the NFL. Top corners make more than top running backs. There wasn't a single running back that went first round in the draft last year just to show you how the value of that position has gone down. Offenses are able to put up more points/yards than ever because of the rule changes. Specifically not allowing DBs to "jam" receivers as much as they used to or hit offensive players like they used to..
http://overthecap.com/positional-spending