Many aftermarket vendors DO offer parts and supplies for non-automotive applications, and traditionally, parts stores have had cataloging and the personnel to find these parts. Considering that the OE parts at a JD dealership counter are often considerably more expensive than the aftermarket parts found in our stores, it can be a great savings to the customer. It is the same reason people choose us over the OE automobile dealer. It only benefits us (both at the store level, and industry-wide) to be knowledgeable about these nontraditional parts needs, and to be prepared to fill those needs. If a customer can purchase candy, soft drinks, and magazines at a parts store, then why should we turn away a sale for tractor parts?
JS Auto Supply
Are you referring specifically to off road equipment and such? If so, they may be off road and used in industries, but they are still automotive at heart. They have an engine, transmission, etc., and they break down also, just like a car. They need parts and parts stores handle that need.