The dreams of inventors and discoverers are more important. This is because these sorts of people come up with things that consumers would never have dreamed of demanding.
An example of this would be someone like Bill Gates. Before Gates created Microsoft (and for some time after) there was no real demand among consumers for a personal computer. However, Gates and Bill Allen had a vision of what could be. From their vision came personal computers, which have helped to enrich our lives in ways that we could never have imagined.
Consumer demand is important, of course. But consumers tend to demand things they already have or slight variations on such things. For truly important change (like the change to a society that is so based on computers as ours is) we rely on the dreamers.