I guess I'm just lucky. We've got shops in our area that actually cooperate ... if someone wants a particular brand that isn't carried at one shop, they send him to the shop that carries it.
Now, mind you, not all the LDS in this area are like that. But the shop I DM for has done it on many an occasion. And I was initially sent to this shop by another LDS when I was looking to purchase a drysuit, and was interested in checking out a particular brand and model. The shops I'm talking about have some things in common. First, they're small, independent shops. Next, they feel that by referring people, they're not losing business so much as demonstrating that good customer service is more important than the sale of a particular piece of gear. It's amazing how often someone will go purchase that gear, then come back and say Thank You, and continue to patronize your store.
By contrast, there used to be another shop just up the street who liked to badmouth other people's products ... but he went out of business.
... Bob (Grateful Diver)