I worked for a landscaper years ago who kept a free ranging rooster which was so aggressive that when we were loading trucks, one person would stand guard with a garden hose. He loved sneaking up behind people and attacking them with his spurs.
I can't imagine tolerating that anyways, but definitely not when running a retail business.
I had one that was getting aggressive with my dog but I tried to get Ruger to defend himself. Then the bird started sneaking up on me. He attacked me one evening while I was feeding and that was his last mistake. I walked out to the truck, grabbed my axe, snatched him, laid his head on a stump and that was the end. Meanwhile my pup's in the back seat of the truck watching, with his eyes as big as saucers.