A drain in the rear corner gives you the largest uninterrupted work surface in your sink. Now, let's look at the issue of right and left handed sinks. If you are right handed and you are cleaning food from a plate, you will hold the plate in your left hand, scrape or spray the surface with your right hand. Having the drain in the rear corner will allow you to slightly turn the plate away from you when you are spraying it. It is reflected back into the sink.
Lefties are no longer second class citizens.
We make left handed sinks without a price penalty. The answer is simple. Actually, there are two answers. The first revolves around inventory. If right and left handed sinks were manufactured, dealers and distributors would have to inventory twice as much product.