In brief, worldbuilding is different than setting in my opinion. Setting is a room. A backdrop. It's scenery. But without good worldbuilding, you can't have realistic feeling scenery. You can't have cool, unique backdrops for your story.
One summer I remember, I got exposed to Chuck Berry and Buddy Holly and Buddy Holly was a very very big, made a very big impression on me. Because of a lot of things, you know, the way he looked and his charisma.