I don't believe in snake oil, however there are good cables and not so good cables and while they can be somewhat expensive, good cables shouldn't cost the earth.
I am thinking more in terms of what I use in my day jobs as a security/comms tech.
You will actually get differences in performance for example with different brands of cat5/6/7 cable. I have have had no name brand cat 6 fail cat 5 spec on a certifier for a very long run slightly over the recommended distance of 90m (110m), a cat 5 cable of a superior brand passed... just. These are measurable results though and it is with high speed data.
Also one other thing is how nice it is to work with, how flexible the cable and it's sheath is, how easy it may be to strip or the sheath resistant to damage, how well the cables are colour coded.
Some examples with that would be again with cat 5/6, some manufacturers don't print the colours on the white mates at all or only very faintly so you can get them mixed up or lose your pair.
In security cable I've had some where the sheath is stretchy and hard to strip, wheareas some powdered cables strip back very easily. Some have more annoying colour schemese, blues that are deep navy and look similar to black, oranges that look like brown, yellow or red.
I've had figure 8 with a sheath that was painfully annoying to strip, very stiff and hard.
With coax for CCTV I've used RG59 before that just wasn't quite right, build quality was a bit sub par and crimp would quite easily pull off when terminated, switched to another brand and the sheath is nice and flexbile but not too soft and of course you can actually crimp a connector on without it coming off.
These are more to do though with ease of assembly.
I do believe that there are differences in quality with audio cables as well as video, however at nowhere near the price of what some people charge, ie. I figure the cost of a patch cable due to it being mass produced should not exceed the cost of that same brand cable by the meter, connectors and labour to assemble plus a small reasonable markup of course.