I think that the bottom line is that if you have a retail store, you want as much traffic in there as possible. Every person that's spending anytime in the store, whether it's just to audition something that he has no intention of buying, is still a potential customer. He might buy something else as he's browsing through the store. A pair of interconnects, some vinyl cleaner, anything. It's still a sale, and a potential for another visit.
You are not going to sell everyone who comes in to kick the tires. I think it's a deep rooted cynicism on the part of the dealer who adopts the attitude of contempt for people who just browse. It's an attitude, nothing more. You'll find that the people with healthier attitudes towards customers, usually do better in business overall, and thus treat people better. It's a chicken and egg thing. You can feel a vibe from a cynical salesperson a mile away when you walk into an establishment.
As someone who's been in business with the public for over 13 years, I've had my fair share of people who have completely wasted my time, and lots of it. But there have been lots of people who have been the easiest customers, and have been repeat customers numerous times that help offset the timewasters. It's part and parcel of being in any business.
While I sympathize with retailers, who are burdened with very high operating costs, I still think that the merchant/client interaction is still a very delicate one, and that a friendly atmosphere is paramount. There are plenty of business models that illustrate this. Chapters bookstores encourages browsing, despite places like Amazon.com, and it works.
Just some food for thought.
Cheers