I've seen chickens inside and I know that mine always wants to come inside with us.. but they do need to go outside too. As said above, they need grass and bugs and dust and sun!! They love it!! Playing in the leaves, running around!
Mine is spoilt and likes exploring inside if we leave the door open.

They are such funny things.
Personally, I wouldn't want a pet chook inside. They poop a lot. It would be kinda gross.

Unless you had a proper set up for it, but just kept it inside.
There is a website that has some awesome chicken coops made in Australia.. there are some big ones that would keep chickens very happy
Also.. chickens like to be in a group.