Our chickens love this treat dispenser!!
I added wooden craft beads to the dispenser to keep the tubes from moving too close to the chicken run wall (see picture). The beads also keep the tubes slightly apart. I had the wooden beads left over from a prior project where we built a chicken swing. I had purchased an assorted pack at Michaels near me for that project and it was enough for both projects.
Do not bring the treats in a bag to refill the dispensers or the chickens will tear a whole in it or take it away from you. I now have plastic bowls with lids (old salsa, feta cheese, or cottage cheese containers) to take the treats to the chicken run. I pinch the sides of the bowl to fill the dispenser. Another option would be to fill a water bottle to transport the treats to the chicken run.