You have already gotten two answers showing why this causes the manufacturer to lose money. A third: I hike, enough that pretty much all my gear out there is the good stuff. I do not care one bit about brands and would prefer not to be an ad for the outdoor companies--but I am anyway because it's not just a name.
Suppose Big Brand X fails to sell all of this year's design and offloads them as discount brand Y. People like me don't want that big X on our stuff, if we learn Y is the same thing we are going to buy Y. And next year their sales of X drop because people like me waiting for the secondary stuff. Thus even if you do not consider brand dilution it's still in their interest to not sell the technical stuff in the secondary channels. When you produce quality a policy of not having sales or setting limits on sales makes a lot of sense.
Suppose Big Brand X fails to sell all of this year's design and offloads them as discount brand Y. People like me don't want that big X on our stuff, if we learn Y is the same thing we are going to buy Y. And next year their sales of X drop because people like me waiting for the secondary stuff. Thus even if you do not consider brand dilution it's still in their interest to not sell the technical stuff in the secondary channels. When you produce quality a policy of not having sales or setting limits on sales makes a lot of sense.