Bigjoe,
Here is my two cents...
It is no secret that fantastic ultra expensive cables are 99.99% of the time totally unnecessary (both for speakers and for interconects and even for very expensive audophile equipment). Just as it is no surprise that these cables can make a lucrative "sell-up" for the floor salesman. People will often spend some time comparison shopping around for their big ticket items but then sucumb to the salesman's pitch "for this latest high $$$ TV/Speaker/amp technology you simply MUST get these appropriate high-end, quality, low-loss, super-duper cables or else you wont get the value out of your purchase!"
For example, in one store I had negotiated a plasma TV and wall bracket at an excellent price, as I came to pay, the salesman explains that the price includes installation. I say great! Then the salesman shows me a wall with the "super duper" interconnects...."only $400 he says. I nearly fell over! I said "you got to be kidding, surely these things normally come with a $3000 purchase...can't you do better?" He goes in the back and comes back looking like I am trying to steal from him...."ok", he says, "for you we'll do it for $300." I say, "I already have cables thank you, and I can handle the installation myself. I would just like the TV and wall mount only please" Then the salesman tells me he cannot sell me the TV without the cabling package...and starts giving me the crap about electrical codes and that my insurance will be invalid if my house burns down. (A very conscientious salesman to be worried about my insurance at home.....but I suspect he is either misinformed or trying to scare me)
I explain that I am aware that running additional 110V power lines/outlets through walls requires an inspection, but I do not plan to do this.... and that there is no requirement or electrical inspection code for low level interconnect signal lines such a component cables and low level audio signals.
The salesman still refused to sell me the TV without the cables and I was forced to go next door where they had a low price guarentee and were nice enough to meet his lower price on the TV. (Although they did try very hard to sell me a power line conditioner....I politely declined and explained that I trusted that Panasonic, a reputable company, had designed the TV with a sufficiently good power supply that I should not have to provide special conditioned power.)
All this goes to show that cables are a meaningful profit generator for electronics stores such that they have an incentive to push you to buy some "super duper" cables (that you don't really need because ordinary ones work fine.)
The only cabling that I have hoenstly found that has some strong basis for paying a little extra is for good shielding, such as with XLR cables. Professionals will often use XLR cables and XLR components because of the shielding and the need for long runs/many criss cross wires in a studio...but it is well known that they don't tend to buy gold plated plugs or special oxygen cables....if anything they tend to pay more for durability and rugged build...given that equipment is often re-arranged or transported and a loose wire is nuisance. So while it is generally true that RCA connectors work very well for the majority of analog signal applications they do have a drawback in that they tend to pick up noise/hum more easily than XLR.
