why do people feel the need to buy expensive cable

The usual reason audiophiles dismiss more expensive cables in a-b comparisons is because to be blunt, their systems aren't capable of clearly revealing the differences.

To summarize, if you can't clearly discern the differences between cables it is probably that your system isn't at the level of the cables, or your maybe ears aren't sophisticated enough to hear the differences. Really...seriously?

10-27-15: Tonykay
To summarize, if you can't clearly discern the differences between cables it is probably that your system isn't at the level of the cables, or your maybe ears aren't sophisticated enough to hear the differences. Really...seriously?

I hope you get the answer you want so you can live on comfortably in delusion. Something about bliss?

I like yuppies. They go buy very expensive stuff, soon after that they do it again, and we have a great choice of cables for 25% the initial cost.
But not all people who buy expensive cables and components are yuppi audiophiles. Some audiophiles on moderate income actually save up big time to get what they want, including new. I don't mean $10k interconnects, $100k amps and $200k speakers. That would be hard to save up for on moderate income. I mean $2k interconnects, $20k amps and $40k speakers. Yeah, most of them buy used.
Besides, there are rich people who are true audiophiles. They just buy what appears to be the best to their ears.
I don't envy them much - they have nothing to upgrade to. Or almost nothing.

Over $1000 for a 1M pair interconnects is certainly expensive, or $2000 for a pair of 2M speaker cables.
In fact, I believe that speakers are no less 'overpriced'.
Do they try to sell furniture or sound when they sell expensive speakers? I guess both. And so double the price - you pay for both. Not to mention that they might cost 10% that figure to the manufacturer.
At least cables by definition are ugly, you can't sell them as a nice furniture too.
But also, why do some think that transmitting the signal with minimal loss and distortion is easy to accomplish?
Anyway, I just bought $1200 interconnect to replace $800 one from $1000 phono to $1500 integrated amp. Stupid, right? Everything was bought used. I'll have to burn it in for 200 hours because it was refilled with Ferox by Purist and then I might report my findings. It is one step up from what I have now, I bet there will be a difference but not big.