I think this is one of ole Job's most misquoted, and misunderstood quips around here. He's not saying that customers walk around in a haze, completely oblivious to what they really want or need. Everyone has a good idea of what they want when they see it.
What he's saying is that customers don't really know they want something until you show them something worth wanting. As in, no one would've wanted something like an iPad until the iPad came out. Now everyone wants an iPad.
He's not saying that customers are idiots. Just that you have to show them the next big thing.