Every mall needs a Mr Bald!
I have only visited the Gallery in Oasis Landing, never built one myself; but this makes me curious on how it works. I tried to build a toy store once, but the sims were very picky customers so the fun part was mostly in setting it up; but then my sim did spent most his time elsewhere chasing other sims so perhaps that was why.
In one save the household owned a bakery, where they hung out every day. That was lovely to decorate, I chose a very flowery theme, sugar sweet with a marriage arch on the top floor. Did not see any inactive sims use it though, but they bought the cookies and pies my sim made (and later on cheat-copied into creation). It also had the Business Time Industrial Oven, selling appropriate dessert food, which also sold well. But I think the lot itself generated money, that must have been separated from the actual sales. I don’t remember the lot assignment (visitors allowed maybe).