If I may be allowed to consider this from a marketer's perspective, then I suppose that for the general public, 'the high end' is a market segment comprising people who seek to own what is perceived as the best of everything. They are brand-conscious, and fill their houses with 'valued' products. They get satisfaction knowing they have bought 'the best'. They may not be super-rich, but they will spend to/beyond their limit to acquire their object of desire. When buying sound systems, I guess they will often buy the best B&O or Bose, or for the few who are 'into' stereos it'd be top of the range Linn, Naim, McIntosh, Rowland etc ... stuff that looks the part ... and has the price tag. If you buy into that perspective, product performance has to be good, but maybe not wholly exceptional, as it is the brand they buy into. They know that top brand + top price = top sound. They won't undertake much product comparison pre-purchase, but will look for third-part affirmation post purchase.
On the other hand, IMO the hifi hobbyist high end is a strange place where the brand catalogue has been defined by self-proclaimed 'opinion leaders' like Harry P / TAS in the States and maybe certain writers, mags and importers here. IMO it is about price, scarcity and exclusivity. It's the collector looking for that 'ultimate' piece .. the pride of ownership. They are looking for guidance and affirmation from their peer-group of hobbyists. For instance, they will seek out a forum of like-minded individuals, who share the same values and beliefs as they do, and seek affirmation there ...