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.
taters
Can I just say something here. There is a DIY audio/audiophile obsession with equipment, cables in particular, being a rip off which people can make in their garage far better. As aforementioned cables from JPS, Nordost, Taralabs and several others are very expensive to manufacture and have a large 'rejection rate'. How many DIY 'hit and miss' bargains do we make? likewise are any of us capable of making an 'air dialectric' or a vacuum cable? Let's also factor in the costs of holding stock, distribution, paying staff some sort of living, shows, and advertising. 
@lohanimal I think you make a great observation. It is a business and sometimes creating innovation costs money. It takes time and a lot of trial and error. Differently materials in different ways. I recently tried to replace a cable with something less expensive and I realized that the innovation of what I had to me was special sound wise. I'm not saying  you can't do well using cheaper I'm just saying that there is a lot of innovation and increased performance in the cable arena.  Some of it is costly. If you can't or don't want to try it then so be it. I just hate the us vs. them in this area. I'm happy for those who can afford it. I'm also happy for those who find great sound on the cheap. Enjoy everyone.
It would appear that air dielectric cables would not be terribly difficult to make, you just need spacers to keep the conductor centered in the jacket.  Now vacuum cables, if there really are such things, is a horse of a different color.  Of course you can achieve the same thing by suspending non-vacuum cables from the ceiling.

My question would be, are they creating innovation for the sake of offering something new each buying cycle, or to really move the ball forward?  I guess when you employ a R&D team, you need to keep them gainfully employed, whether they launch a rocket every year, or not.

I remember downhill ski manufacturers coming out with "new and improved" skis/bindings/boots every year (sometimes just a different color scheme), and every year, the guys who could ski really well, could still ski really well, no matter what they were skiing on, and the others, well, you get my point.  When they came out with parabolic skis...that was a true rocket launch.

I understand about incrementally moving things forward and such but the consumer pays the freight for all that R&D, and trial and error and, I think with cables, the issue is whether the actual sonic improvement is worth the extraordinary cost of some of the cables being sold.  However, for those who have and want to spend the big bucks, carry on.

Hey Mitch - you probably have some point here - I think that .is 'across the board' of an manufacturing industry or process. If you read an issue of HiFi Critic Martin Colloms is very honest insofar as he will say a previous model is better than the current model. In some cases there are sometimes backward  steps, however, newer models of a type of component usually bring improvements. What I will say, however, within components. some parts are not available or manufactured, or there are restrictions so new is not always better - ie the JFets in the Vendetta SCP2A, the new lead free solder preventing the manufacture of the Connoisseur pre-amps - likewise explaining that KRELL took awhile to get their amps to sound good with lead free solder.
I personally take my time before any changes - in fact it took me around 10 years to fundamentally change my system, and that has been in the areas of speaker cables, and a dedicated mains - wish I did it sooner.