Nope, I accept that orthotics can work in some circumstances, because the research performed supports this. Unfortunately assuming that support shoes also work is conjecture and there just isn't the evidence to support it. If there was you can be sure that all manufacturers of support shoes would be referencing it. There's also a risk of assuming the evidence that supports orthotics is for the same ailment that the support shoe is proposed to prevent. So for instance there's evidence that orthotics reduces pain assoicated with plantar fasciatis and metatarsalgia (though not limited just to these two conditions), neither of which to the best of my knowlege are things that support shoes pupport to fix. This is the danger of assumptive leaps. Also on the assumptive list I haven't ever concluded that they don't work - I think you may filled that conclusion in on my behalf. I've only ever said there's no evidence that any running shoe technology works - it's an important difference, and one that the shoe manufacturers are generally aware of, so they make statements such as 'now with extra dynamic support' and the punter fills in the gap and infers that this must be a good thing despite the complete absence of evidence from the manufacturer to support this inference.
Likewise the statement that the fact the running shops do business is itself practical evidence their methods work could equally be applied to homeopathy. It may seem a disingenuous comparison, but both are still in business, both genuinely believe they are doing good, and both believe they see evidence on a daily basis that they are doing good, and in both cases their customers also believe they are doing good. And both come unstuck at the evidence based research stage.
Running shops have a product to sell - there's nothing wrong in that, they just need to think a bit smarter about the process and claims that they make. If they want a USP, rather than saying or implying 'these shoes will reduce your chances of injury', they could focus on 'these shoes (or if more canny, upsell to this running clinic) could strengthing your running muscles. That said I don't know if there's any evidence to support it, but it is at least another avenue for them to explore.
At least you didn't trot-out that most-maligned of scientific studies; that by the US military that shows no conclusive proof either for or against support shoes, but which barefooters invariably alter to suggest that they don't work. I am sure you know what I'm talking about - barefooters always mis-quote it.
Actually I was going to use that one next : ) This no conclusive proof either for or against support shoes, is the crux of the matter though!!!. People in shops selling crap for which there is no supporting evidence, yet claiming that it reduces injuries - this goes for Vibram too with there patently daft quote that their shoes reduce injuries.
Given that no-one and this is worth repeating, NO ONE has ever produced any credible research that shows the technology in their shoes reduces injury rates it's a pretty safe assumption that their isn't any technology that running shoe shops sell that does this. The one proviso being orthotics, but that's a job for podiatrists, not shoe salesmen.
Shoes are great! Faux techno bollocks spouted about them isn't.
Next point - people ran without technology, but not as many people did well at it. Technology allows people with flat feet, fallen arches and severe gait problems to run, whereas in the past, they wouldn't have been able.
I'm pretty certain running shops don't sell 'technology' that can do this. I can't recollect seeing any research that backs this up iether.