3D printing in plastic will not work - the plastic will deform, it will grow bacteria and be hard to clean with inherent step lines in the 3D print and the material not being dishwasher safe. The only workable material is 3D printed ceramic, available at services such as Shapeways. This is foodsafe and since it is post-glazed it is cleanable and has a beautiful smooth finish. It comes in several colors and adding a logo will not significantly change the price. You can even make the bowls customizable. Cost per bowl: US$ 50-100. The cost is fixed per bowl and does not change much with quantity, unlike with molding processes where you pay fixed costs for tooling. I recommend to go with 3D printing only if it is absolutely necessary to create a unique geometry or customizability and you find people willing to pay, say 10x more for this. You can also consider hiring a sculptor or potter.