Are audiophiles people of sound prejudice?

ONLY if you think YOUR priorities are the ONLY right ones! Mine ARE, in MY listening room. Natural and balanced ARE, in the venues I set up(according to my clients).

Yes, sound prejudice and price snobs against cheap gears and cables...

Yes. Certainly.
All one has to do is go to any high end event and listen to the myriad systems on display and the loyal followers, the know it alls, the disparagers, and the ones with the bemused looks on their faces. We all know what sounds good to us from the journeys we've taken and it can only be seen through the prejudices we have developed.

I really like your question and the way you framed it.

I agree, we listen with our ears and can only really know
that single certainty. We listen with others and to others
systems, but we listen with biased tastes. Like eating a
great meal, certain flavors are more endearing to our palet
than someone else's. We base our opinions on many things but
mostly inner ego, or what satisfies us. Is that prejudice or
just selfish behavior, or are they the same?

Yes, I think audiophiles are sound-prejudiced. Audiophiles pre-judge based on the expectations and preferences of what sound quality is, built up over time. It's human nature. Being an audiophile is about sound quality and audiophiles are very discerning of it. Because the equipment is very sensitive and does not guarantee success when putting a system together, our prejudices make it complicated to achieve the sound quality desired. Audiophile systems are by their nature, not plug and play. There is typically trial and error involved in the process of building a satisfying system. Sound prejudice has much to do with the entire process.