It's hard to "think like a chicken," but that's what we need to do at times.
I stay away from treats as entertainment, with one exception, and that's snack time in the afternoon. But their "snack" is their regular food wetted into a mash, so it's really just a separate meal. They think it's special, they look forward to it, it's "entertainment" to them. They come running when I say, "Chickie snack!"
@3KillerBs has a great example of run clutter. To Aunt Tillie, it might look like an eyesore, a mess, a bunch of junk. To the chickens, it's their playground. Stuff to climb on! Stuff to run around/behind/under! And, best of all, stuff to scratch through!
The more I sit and watch my chickens, the more I see them scratch at the dirt. So I try to make the dirt interesting to the chickens.
Just like bored kids have behavioral issues, bored chickens have (chicken) behavioral issues.