We are the ones spending our money for our personal enjoyment. Not sure why some feel the need to try to convince us it’s bogus. You’re not spending their money, nor asking them to either.
Bingo!
One reason I hate this double-blind debate so much is its so unbelievably misguided. There's a time and a place for everything. Some guy like Ted Denney or Keith Herron, both of whom do use double-blind testing, they have a reason and they use it correctly. The idea, which I know for sure in the case of Keith who I talked to about this, is to test and see if there is any preference at all, and if so which way. These test subjects do not even know what is being compared or tested all they do is indicate whether they prefer one or the other or no difference.
In this case testing is justified and valid because the goal is to develop a result a wide range of people will like. So it only makes sense to test a wide range of people.
The situation with cables is completely different. Its one person buying one cable for themselves. What does that person care for the opinion of some random interboob?