Overhangs add more counter space for you and make seating more comfortable because you can slide your knees underneath the overhang.
Supports Old bar countertops are usually supported on plywood which is screwed into the stud wall and is normally not strong enough to support granite. Granite can weigh up to 20 pounds per square foot, so it's important that it is supported properly.
The first option for supporting this extra weight is to use corbels of metal or wood. These work well and add a design flair to your project but they may hit your knees if you are sitting at the bar on a stool. Corbels that match your cabinets are normally available from your cabinet supplier.
The second option which GQC uses are steel "L" shape supports. These are made from ¼" thick solid steel. A shallow ¼" deep slot is routed into the top of the supporting wall allowing the horizontal bar to be flush with the bottom of the granite. The granite is then adhered with 100% silicone to the wall and the horizontal part of the steel support. This method results in an almost invisible support that, unlike corbels, protects your knees. With the vertical bar in the wall or cabinet and the horizontal bar covered by the granite this is a strong unobtrusive option.