It's not about Peta. It's a bunch of fisherman who got together and came up with ways to ensure that there's gonna continue to be great fishing here for decades.
Hell, you can't even fish with bait.
Simply having a barb on your hook results in something like 15 or 20% of the fish end up dying from the trauma. From time to time I've forgotten to clamp the barb down, and trying to get a fish off one of these things can be ugly and time consuming. You half rip the fish's face off.
You don't see many guys here catchin' fish to eat them. In fact it's pretty taboo, and the guys that fish with a spin caster, a club and a cooler, while rare around here, are viewed as complete tools. It's a pretty serious sport, and the Bow River is probably in the top 5 trout rivers in the world. I'm pretty thankful for these rules... the fish are HUGE and there's lots of them. So what do I care about the rest of it?