The public don't know what they want! ;) Problem is they'll settle for naff quality because they don't realise exactly what kind of quality can be achieved from the technology, they merely accept the broadcasted quality because they don't believe they can do anything about it, and there we have it. If you ask the early adopters what the quality was like at start as opposed to today, they all take our standpoint (it's rubbish now).
Part of the problem is that what one person might hear and what another person might hear is different. Whilst I know some people who can, personally I can't tell the difference between DAB Radio 2 and FM Radio 2 broadcast via the same set. Actually that's a lie. I can. FM is the one with the fuzz and hiss. TV pictures are a similar one. You wouldn't believe the number of people who can watch 4:3 signals on Freeview, stretched out to 16:9 on a naff LCD and think it's the best picture they've ever seen. Yet it makes me cringe every time. But try telling people that you're right... ;) And lets not forget that we've now got a culture growing whereby teenagers listen to music via appalling mobile loudspeakers on buses (well that is until I loom over then and threaten to ram the confounded thing down their throat anyway! ;)