While everything makes a difference, does that mean better? As pointed out by many here, science does suggest that Material quality and shielding makes for a better cable. It may cost hundreds of dollars to produce a cable with the properties desired to produce audiophile grade sound. What makes me scratch my head in wonder is seeing $7k power or $30k speaker wires. I suppose enough market exists among the Less than 1% crowd to keep some of these in business.
Then again, nothing new under the sun. Some of the claims thrown around remind me of the early 70's first fuel shortage. Reading about all the miracle fuel saving gadgets coming on market would lead one to think that you may need to tow a tanker to collect all the extra fuel you would be making.
At the end of the day, only so many veils can be lifted before it becomes a gadget obsession instead of a music hobby.