I'm just going to throw a scenario out that has happened to someone I know personally.
Bird owner has birds that are not penned and free roam a suburban neighborhood; a subdivision with a large pond in the middle of it. Neighbors get miffed at bird owner for some reason (whether bird-related or not, I don't know) and start collecting written complaints from other residents against bird owner. Ticked neighbor goes to town board with complaints. Back and forth ensues. Town board ends up filing lawsuit against bird owner for "damage" to the town done by birds for a ridiculous amount of money (over 10k) that included punitive damages because birds made the resident's lives a living hell. Judge ends up siding with town board, leaving bird owner in a heck of a situation.
Lawsuit was a complete sham and a waste of time. But it just goes to show, you tick off the right people and you have a huge problem on your hands. It seems the biggest jerks usually know the people to get their way. Hence why they're jerks. A problem that was completely avoidable, all because you didn't want to spend the time to build a secure pen for your birds.
The simple fact is, some people don't like animals. Personally, I think those people are nuts but hey, to each their own. However, if I lived in a suburban area I wouldn't expect to find a turkey or a guinea in my backyard and it is simply unreasonable to expect someone to be fine with it. I love free ranging my birds, but you cannot visit your hobby on someone else.
OP has stated once that the birds wouldn't dare go to a neighbor's yard, then turned around and said the only time they'd hop the neighbor's fence is when they would be curious, but would only be pecking there for a minute. A minute is all it takes. Plus, if you really think free range birds will stay only in one place i.e. the forest area, you're frankly dreaming. If there is one place you don't want them to be, they will make it there eventually.
You can say humans have been letting animals graze on public land for thousands of years til you're blue in the face. When that code officer shows up with a fat ticket and you tell him that, he's going to take that ticket and stick it in between your eyes.