If you poke around the investors' section of the GW website, it's kind of revelatory. They seem totally focused on selling as many minis as possible through a strategy of isolating and targeting those individuals who buy the most minis. Their business model is available
here.
What I find odd about it is how vehemently they say they are a manufacturer, not a retailer, and how they never refer to "stores" but instead to "Hobby centres." My guess is either they are pushing a "lifestyle" approach or there is some important legal distinction in the UK between stores and not-stores
If you look at the link, I also strongly recommend reading the Chairman's Preambles (to the annual financial reports, available from a link on the left of that page). They give a veiled sense of the company's ups and downs and some sense of what they think they are doing.
It seems clear that the people running the business have no interest in or sympathy with miniatures collectors except as the particular sort of client they are catering to. Their core customers are described to the shareholders pretty condescendingly as having a peculiar obsession with accumulating of hundreds of little toy soldiers. While there is a constantly repeated refrain of GW's "wonderful" minis, the "best in the world," they are treated abstractly as the generic product GW happens to produce.
Games Workshop's sales improved last year after a slump. I don't know that the "supply of fresh meat" is actually shrinking. I suspect that as long as Games Workshop keeps getting new little boys interested and buying lots and lots of their product the concerns of any number of dedicated older fans will not trouble them.