why do people feel the need to buy expensive cable

There are some basics when it comes to cable that can be measured. Then there's everything else that can't or is on the cutting edge of what can be known and demonstrated. I think the question is whether the price of admission to 'what if' is what should be debated.

Some answers in the affirmative can justify a price increase if it's labor intensive or if it requires some exotic metallurgy. Some answers that still remain in doubt should be looked at with a discerning eye (and ear).

Through all the years in audiophile history there have been some killer systems that used some old, tried and trued cables that did the job. Some basic tweaks along the way with coatings, purity, dielectrics, etc are probably all that were and are needed.

Interfaces between amp and speaker should be taken into consideration as well. Beyond that, I"m at a loss to say.

All the best,
Nonoise

The purchase of a luxury good may or may not make the purchaser happy, but it does make them happy about themselves. It's an affirmation of how they see themselves and their position in society. It's a testament to someone's economic status and discernment. Notice that the two most common rebuttals to those who question the wisdom of expensive cables are variations of "you can't afford it" and "your system or hearing isn't of high enough quality to judge".

Mapman, obsess much about what other folks spend on audio?

Sometimes a cigar is just a cigar.

"Mapman, obsess much about what other folks spend on audio? "

Not at all. Absolutely zero. I didn't ask the question. Just offering my opinions like everyone else, dear.