Cable pushers use a couple of very common but very effective tricks and plays on perceived wisdom.
The first and most important one is that the most effective lies are based around a kernel of truth, this anchors the lie and propaganda masters and political despots have always understood that if you want to mislead people and convince them to believe stupid things and generally just swallow untruths it helps awfully if you can make reference to something that it true. Whether or not that truth is germane to the matter at hand is completely irrelevant. Remember, we're trying to convince people to part with $$$$$$$$$$$$$$$$'s to buy hideously expensive snake oil, we're not here to educate. So for example a well made cable with high quality connections and materials can be expected to be more durable. Cables do have to be suitable for the load. The infamous skin effect which cable freaks obsess about is real. By tying your spin to some of these truths it gives you greater perceived credibility and allow to sow confusion by throwing this stuff into arguments as a weapon of mass distraction and putting conflating myth and reality in the minds of the gullible.
Secondly, develop ideas which are perfectly reasonable in terms of lay persons intuitive understanding and which fit well with the sort of analogies used to simplify understanding of complex ideas which don't hold water but which are cleverly crafted to dupe the easily impressed by making them feel more clever and informed than they are. This works particularly well on magazine reviewers and the media in general. Take a look at almost any magazine reviewer trying to sell the benefits of high-resolution, multi-bit DACs, analogue etc and you can generally recognise the spin which has been spoon fed to reviewers by manufacturers. I regularly read media articles on emissions for which I recognise the syntax and know who supplied the words (and it isn't the journalist claiming to be the author).
One of the most simple tricks is to play on peoples natural sentiment that if something is more expensive it should be better. This is something most of us suffer from, and in many aspects of life it is perfectly true that quality costs and as you go up the price scale you get a better product. This is also true in hi-fi, for example Accuphase equipment has never been cheap. However many brands in hi-fi have exploited this and created a demand for poorly engineered, shoddily made tat.
Develop the sort of affable everyman persona which convinces people you're a straight talking guy, it's amazing how people will believe somebody that they like and who pretends to be a straight talker even if they're a manipulative and deceitful prick. Lie with conviction and say it in a nice way which appeals to people and it's amazing what you can get away with. Manipulate peoples sense of identity and create a perception of being part of a group and an insider with privileged knowledge and understanding. There is a good reason so many manufacturers of so many different goods invest the time and effort necessary to participate in internet forums, making youtube videos etc, it is an extremely effective way to play on emotions and create brand loyalty and suppress reasoned analysis as people get dazzled by the thought of having an inside track to the man.
However even with that it's quite hard to convince people to believe an absolute lie (although plenty can pull it off) hence the need to hang these things onto a kernel of truth and/or arguments which can make perfect sense in isolation. So for example, it seems eminently reasonable and sensible that a clean electrical supply will improve hi-fi performance and to then develop this into creating a demand for power supplies costing $$$$$$$$$$$$$$$$'s. None of these tricks are new or unknown to most people, but they still work and are very effective. And of course, the value of tame magazine reviewers who know what's expected of them should never be underestimated.
And as I write all that, I look at these people making a tidy living and basking in the glow of adulation from their fans and ask who are the idiots in this world really?