Has little to do with pedigree or price. That's the simplest case of expectation bias. The much larger problem, ignored by most 'sighted' audiophiles, is that our ability to compare and contrast audio quality is just not good enough to do any comparisons over 10 seconds or so. The brain isn't developed to evaluate and recall perfectly audio quality. It's developed to recognize familiar sounds and to pick them out of messy, noisy environments. That was (and sometimes still is) the key to our survival. It's a pattern matching machine that often fills in the details that may be missing using all other senses and past experiences. Hearing is much more driven by sight and knowledge than we recognize on a conscious level.
If you don't do these comparisons without knowing which device is playing, you're not testing with your ears, you are testing with your whole brain and memory, and that has huge effect on the outcome of the test. To claim that you can somehow turn off this function of the brain is silly. Not only because that's extremely hard to do, but because nobody, including you, knows for sure if you are actually able to achieve this mental state.