Yes, people have different tastes but I think people who 'know about' wine, cheese or whatever it is would universally prefer a high-quality product that's been made by people who know what they're doing, to something very cheap and mass-produced. And yes, someone who's not knowledgeable about wine may not see 'what the fuss is about' over an expensive bottle, but let's suppose he then goes on a wine-tasting course; unless there's something actually wrong with his tastebuds, he'd be then able to tell a grand-cru Burgundy from a £5 Turning Leaf merlot. And if the woman buying Nigella-approved cheddar were to do a blind taste test, she might well find there's another cheese that's tastier and perhaps not even any more expensive - in this case, the Nigella Lawson Seal Of Approval is like the logo on the T-shirt; it adds a purely psychological value that has nothing to do with the inherent quality of the product.
Another point is that there are two reasons why a given product might cost more than a comparable product. There could be a supply-side reason, in other words the first product actually costs more to produce the second, because it uses higher quality raw ingredients, has to be made by trained craftsman, has to be matured for a long time, is only made in one place rather than factories that can be built anywhere, and so on. This is why single malts cost more than blended whisky; they're actually that much more expensive to produce, but people buy them because they're a better product.
The other thing that affects the price of something lies on the demand side. This is our T-shirt, handbag or whatever that is perceived as valuable because it carries with it some sort of cachet, which is then bestowed on the person who wears/carries it. So a T-shirt might be made more 'valuable' by having a logo stitched onto it, which costs very little, whereas for a cheese to made more valuable, it has to be matured for a couple of years in a special facility with a controlled temperature and humidity, which is very expensive. So if the label in question went out of fashion, the company could still make a profit (a reduced one, of course) by dropping the price of its shirts, because it was working on a high profit margin and can still be profitable even with a smaller margin. Whereas a mature artisan cheese cannot be sold at the same price as a processe cheddar because of the inherently high cost of producing it.