My daughters did this with their girl scout troop a quite a few years ago and had a blast. I would say its a great place for kids to have a party that are between the ages of 7 and 10.
The animals and clothing come in all different price ranges. You can put a limit on how much each child spends by giving them a limited choice.
To the best of my knowledge they do not have an area for serving food. You could bring cup cakes, and serve them in the food court.
My recommendation would be to have the kids come to your house. Then you and hubby can transport them to the mall, go to Build A Bear, and return to your home where you serve cake. I would also recommend 10 kids max. Keep in mind that even though your having a party, the store is also filled with other customers.