My flock and my neighbors flock will sometimes all mingle together either in her yard or ours. Never once had they gotten into a fight and they love foraging together. We have a lot of bugs here too. So many bugs, their feed ends up in the compost pile after a while. My flock won't go inside their coop, but I've seen their flock inside mine. Neither of us mind, but i find it quite odd since i thought chickens were territorial. We both have had our flocks for a few years. I add new ones every year and they add new chicks every 2 years.