you can have chickens who do not eat your veges. first of all, learn to see them as blessed wonderful beings, and learn to provide for their needs, their real biological needs, and not needs invented by business.
1 create a scratch patch – one that is especially for them – a patch of delicious ground that is full of worms and micro-organisms. do not put a mulch over the patch – very important. so in that case the patch needs to go under the shade of some trees.
2 give them access to their natural food instead of food scraps – and bread and any other processed food is definitely out! let a patch of the grasses grow. they jump up and eat the tiny grass seeds, berries from the nightshade bush commonly found in australia. they are delicious. let them grow.