Sure, you can sit in them to draw or write or work puzzles or play games.
Sure, you can sit in them when learning together in group time.
But chairs can be used for a lot of other things, too. Just look at how we've used them.
To hold our writing box
Or to hold other things for a center
As a waiting room/doctor's office
As a car
As a boat
As an office/desk chair
As a church
Chairs can be great for a lot of fun things. How have you used chairs to be something else?