Style, like most poorly understood things, often gets a bad rap. We spend a lot of time engaging in style making behavior and even more enjoying experiences of style, but most people probably can't describe what that "does" for them. It operates on a level that is difficult to define and measure, but it is an incredibly rich source of many of the things we enjoy in life.
Style is usually defined as "the way you do something". A lot of pop music is an exercise in styling. The length, chords, rhythms and themes don't vary nearly as much as the "kinds of sound".
Here is one of the finest examples of the power of style, it's Eddie Izzard talking about Darth Vader's voice in Dressed to Kill. (Sorry, it comes at the end of this 5 min clip.)
Can you really put a price on what the voice of Darth Vader is worth?