Warm water fishing: Do you Brownline?

Last thursday the Wall Street Journal ran a piece (view it here) on fishing for carp, catfish, and other warm-water species using a fly. They talk about a term completely new to me called "brownlining" or finding the brown lines on a map like urban creeks, rivers, and ditches. I guess the term's heritage flows from "bluelining" or looking at a topo map and picking a unnamed creek (blue line) in the wilderness and following it for fish. In this case you're looking for the brown water. The WSJ goes on to portray this type of activity as new to the sport. Funny, I thought this was just called fishing and as far as I can tell it's been going on for a long time now.

Unfortunately for me they concentrated on a stretch of water that I like to fish quite a bit. The South Platte right through Denver. Yes, the river is dirty and there's diapers, shopping carts and trash in the trees, but who cares... In my book fishing is fishing. If you love it, you do it when you can, wherever you can. My guess is if this had been about spin fisherman it would have never made the Wall Street Journal. Why is this even a story? Just seems like some dudes going out fishing close to home for a couple of hours. My question to you is why do fly fisherman get this bum rap of highfalutin, nose in the air sensibility just because they're not fishing for trout?

TR