That's a bit harsh. IMHO people don't know what's even possible, so they can't tell you what the solution is. Sometimes they can tell you what bothers them about what they've got even if they don't know what would be better. The rest of your comment it good though. Watch them. Look for things that look hard or redundant. Ask if they ever get tired of X, what gets in the way, etc... But don't necessarily expect them to tell you how to make it better.

I like to say users don't have requirements. They have problems.