For some people, less is sufficient, less has less confusion, less feels lighter and less is more-than-enough. I agree and for good reason: they've been trained to think that way. May be they advocate pareto's 80-20 rule, just do the 20 percent - the less is more.
But most people want more, they need the extra one feature which may not wanted by most - they really want the long tail of features. The 'more' should not spoil the experience they had with 'less'. Should not complicate the user experience introducing the more. What they really want is More features at the experience of Less - they expect more..
This drives to analogize with the classic example of longtail; Wal-mart and other major retailers don't carry less popular albums (they carry less, the top 20 percent). The Rhapsody demand, however, keeps going. The rare songs find an audience, there are people looking for more. But impossible for vendors like Wal-mart whose physical inventory business model just restricts, to offer the more.