How would you like being in a cage for your whole life with nothing to do but sit there?
First of all, most fish in tanks wouldn't survive being released solely because of the temperature shock. Secondly, fish have been finding food by themselves for thousands of years. If a lost dog can figure out how to hunt, I'm pretty sure a fish can too.
That makes no sense. Fish can't be domesticated. They can be trained, but that's not domestication. COWS are domesticated. Fish are fish. And no I'm sorry, but fish will adapt. When they realize food will not be coming they will try to eat other things. Just like a dog, cat, mouse, or chicken.
How about you prove it. You're the one saying I'm wrong, so let's see some links to information. The burden of proof lies on the dissenter. You say fish are so stupid they wouldn't remember how to eat outside of a tank, come back with a REPUTABLE study, and link it.
I am, all I'm seeing are "Salmon running the gauntlet" on PBS from 2011, and some very technical stuff from the NOAA about broodstock technology. However since there's been very successful breeding programs for other fish in my area and releasing them into lakes and river, I'm inclined to say you may be remembering things wrongly. Anyway, captive bred fish aren't the same as pet fish you get in a store. Most of those fish are tropical, freshwater, very sensitive to pollution, and wouldn't survive release let alone be able to starve. I can't find it, so unless you know what episode it was, when it aired, and what show on PBS I'm drawing a blank.
Until someone throws a fighting fish in the tank.
Not really...they're captive...