Your zoning code seems awesome! Do people seem to go crazy with the slack?
Surprisingly relatively few people here keep livestock or poultry here (compared to the amount of space available) as there's a lot of retirees living here who've aged out of wanting to manage them, and young families who just don't have the time.
As far as chickens, I know there's a few people around with flocks, but I haven't seen/heard any evidence of anyone keeping large flocks. Biggest I've seen is a mixed flock of chickens, ducks and turkeys that number about 30 birds maybe. I think the zoning is a reflection of the roots of the area, as this used to be farms and agricultural land... my lot was part of a goat farm at one point, so I've been told.