Sharing Apple TV

Purchase sharing is optional though. You can have Family Sharing (including shareable subscriptions) without purchase sharing (for buy-content) — if you prefer.

How to share purchases with your family - Apple Support

Depends on what you mean by “access to your apple store”.

Will you get charged for their purchases? Yes. Unless they have gift card credit balance.

Will their purchases show up on your purchase history? No.

Will they be able to see, download and watch your past and future purchases? Yes.