Once Tower/Great Planes obtained the OS import monopoly and raised the selling prices Sheldon ended up buying the OS line through Canada to circumvent the Tower import monopoly. They sold them for less because they bought them for less. Ended up almost going to a lawsuit, if it didn't actually do so.

H/S did discount their pricing quite a bit, and even gave customers discounts for buying in larger quantities. Unfortunately in a lot of areas they were undecut by someone (you know who) deliberately selling some things for less than they cost whoelsale in order to start getting a corner on the market. A dealer cannot compete against their supplier unless their intent is to go bankrupt.