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
I've been in this hobby for more than 40 years and have, over that time gone the expensive cable route.  Those are all gone thanks to a friend who builds world class amps and pre amps for a living.  I now run 16ga Duelund tinned copper for my speakers and Duelund 20ga for home made ICs.  The RCAs are $4 switchcraft.  The sound is incredible.  Musical and open.
I'd never knock anyone who has the resources and desire to spend more.  We all make choices.  
I don't get the Porsche analogy though.  How can one compare something mechanical to something passive?  Of course higher grade parts on a machine will make a difference.  But on wire?