Absolutely normal. Chickens are greedy, self-centered buggers, especially the hens. When one has something, the others will do their darndest to get it from them. This is how egg eating gets started in a flock, by the way. Hens watch each other like hawks (pardon the pun) and horn in on anything that looks like a free meal.
It doesn't matter that there are other goodies lying there, either - now you are inferring logic, for which chickens are not well known.
But, and this is no small matter - this is where chickens become entertaining. Take a lawn chair, a piece cheap bologna and a cool drink of your choice and go out to the chicken pen. Sit in the chair and peel off small, wormlike strips of bologna. Toss these to the birds and watch the pandemonium. You thought grapes were fun? Boy howdy, wait'll you try the lunchmeat.
Someone will always mention the salt and nitrates in the bologna at this moment, throwing a wet blanket on the whole party. While my chickens never fared any worse for a few bologna strips, do as your conscience dictates.
There is one caveat in all this fun, though. Treats should be fed sparingly, so as not to disturb the nutrition they receive from the rations you feed them. They are sensitive to disturbances in their feeding routine and you should be mindful of that.
I don't want them to hurt each other to get one thing when there is plenty for all of them.
