why do people feel the need to buy expensive cable

I have tried expensive cables and one's moderately priced. I would say there were some differences but I can't actually say the expensive cables were better. IMHO I believe a lot of people buy expensive cables because they don't actual trust their ears and are afraid of making a mistake. They figure the expensive cables are better for the fact they cost more. If you have a difference of opinion or share the same thoughts, I would like to hear about it.
I buy and enjoy used components that hold their value for years. Key is buying from a mainstream manufacturer with a big (cult?) following, good support and longevity. For me that is ARC, VPI, Nordost and Vandersteen. In that light, cables are as much an investment as is an amp. Buying at half price I'm not going to loose much. The demand will always be there. Currently I'm running a tweaked VPI HW-19 MKIV/JMW with Ortofon Cadenza Bronze, ARC PH7, ARC REF3, Ayre V-5xe and Vandersteen 3A Sigs. They are strung together with Nordost Frey2 interconnects and a Acoustic Zen Satori Shotgun SC's. An engaging system. Recently I was Blown Away by replacing the IC between the pre and main amps with a Nordost Tyr 2. That IC breathed a life and magic into my rig that is the Holy Grail we all hope for. It is without reservation the biggest leap in system satisfaction I have ever experienced. In addition to the Frey 2, I have lower priced cables around the house by Kimber, LAD, Audioquest and Zu. They can't touch the Frey 2 by a long shot. The Frey 2 can't touch the Tyr 2 by along shot. On a (much) lesser system all these cables sound a lot alike and I would not bother with more than a very basic entry cable by Audioquest. It's not worth it.
why do people feel the need to buy expensive cable
Because in some cases, they sound superior.

In my system, I use a combination of PCs. 2 that were custom made at $175 each and the rest Nordost Valhalla, High Fidelity and Shunyata Sigma.

I build my AUDIO system base on SOUND QUALITY and NOT status, measurements ... I use my EAR and buy what sounds the best!!!
Thank you for making my point Professor825.
1. the eye
2. the mind

Anyone wears Prada?
I'm off that particular merry go round. My system has only the very thin wires connecting the lightweight earphones to the portable player. I eschew all other cables, interconnects, power cords, digital cable, what have you.