The fact is, I find it very frustrating that there is so much one sided, biased information out there. So much in fact that it is near imposable to find the "truth" on any controversial subject.
Over the past three decades, I have found the most accurate way to get information is to take what you read in "studies" and throw out everything that could possibly be opinion, just look at the facts, like (example) so&so group counted 500 wolves in the greater Yellowstone area, then figure that they are stupid, so if they counted 500 the real number is probably more like 800. Then use common sense. We know (at least I believe) that the elk is THE #1 pray species for wolves, and 800 wolves means about 80 packs, and a pack of wolves probably kill about two elk a week, one adult and one calf. Then do the math. 80 packs X 2 elk X 52 weeks = 8320 elk per year (4160 adults & 4160 calf’s)
I know this involves a LOT of guesswork by an armature (me) but I have found that eventually, facts come out, and the beliefs that I have formed are usually more accurate than the crap that has been spred by the "professionals".
Regarding the above theory, that wolves provide a great economic impact, there are just too many variables to make that claim, so I call Bullchit. OPEC could decide to have a secrete conference in the Yellowstone hotel, spend a fortune at the bar on Gray Goose martinis, and somebody would say, "look at all the money we made, it must be the wolves!