Yes, indeed, they do, in all consumer marketplace, not just in audio. Marketing science is a high skill, been practiced for centuries.
Anyway, all I can tell you is that when I upgraded cables, especially my Kimber D60, the music sounded fuller and richer. Or perhaps my mind just believed so because I paid more for it...
This is what science can test, to see if you really heard what you think you perceived. But, it would be under a bit different circumstance than what you did. Since this is sonic differences you are testing, you will not see which component cable is played for you, you would have to guess that it was the D60, and do it 15 of 20 tries with random swaps. To date, no one has succeeded. But, who knows, you may be the first on the planet. This is what science does, very well.
Oh, who knows why your biases chose that D60. Maybe it was the looks, the numbering, any number of reasons it convinced you.
This Stereo Times article argues the same case. (Funny and EXCELLENT article)
http://www.stereotimes.com/cables042501.shtm
END OF THREADJACK FOR ME...
No reason to argue. Test your claim under DBT protocol. You could be the one.