They are both equally important.
The smaller areas feed into destination areas in two ways:
1. They provide an introduction to the sport and a training ground for people who later move to the big areas.
2. They deliver a good number of the occasional visitors, for a week-long or even a weekend trip, to the destination resorts.
Without the small areas, there will simply be fewer opportunities for people to get started in the sport. People won't just go straight to the destination resorts, they will more likely leave the sport altogether.
The destination areas complement the small areas perfectly. They provide a change of pace and a new environment that maintains long-term interest in the sport. They provide a challenge to look forward to, and a reason to get 20 days of training in at the small hill to make the big mountain experience more enjoyable. They provide an opportunity for "cross-pollination" as people from many different regions meet in the major destination areas.
Without the destination areas, the local experience becomes a bit more limited. The local hills become more insular, without the new ideas and even just the stories coming back from the large destinations.