Turns out it's okay nutritionally to feed ducks (for example) fresh (thawed frozen) peas. Just not bread. Changing their habits might be a different consideration.
Yea, generally when people feed animals it is harmful to the animal or potentially dangerous for humans in a variety of ways or you turn the animals into pests.
Is there something special about crows where these things aren't so much a factor?
I think a lot of it is the high intelligence of crows. If you feed say, wild deer or other animals they become dependent on humans to survive or end up sticking around human areas. Crows are already everywhere and their intelligence means that if the food source stops, they can still just do their thing. It doesn't disrupt the ecosystem though it can make them into an annoyance for neighbors.
The more we learn about crows, their behaviors etc the more we realize that we severely understate their intelligence with each new finding.
Crows are generally a pest inhibitor, given that they will eat carrion before less desirable "pests" like rats get to it.
They also already are adopted to living in human cities. Usually in parks where they can do some traditional hunting intermixed with trash collecting and some direct feeding. But they are usually not reliant on the later and will move on in Winter if the other sources dry up.
