Fashion From Region to Region

One of the things I am excited to see when I go to Italy in about two months is all the fashion.  Italy, especially Milan is known as being a center of fashion.  Large scale fashion designers like Dolce and Gabbana, Prada, Fendi and Armani sell their products throughout the world.  My question is, how is it different from region to region and even city to city?

Each location has a different mix of people.  A city may have different attitudes than a suburb.  People in a suburb dress differently than those in an urban environment.  Therefore, these designers have to come up with multiple collections to fit these markets, right?  Or, since these designers are considered high class, can they afford to only make a limited number of lines?

How do other designers differ?  Do more affordable designers have different collections based on region?  How does that work?

Attached to these product lines is the subject of how they market them.  Here, it definitely differs from region to region.  Take a more affordable brand, Victoria’s Secret, for example.  They have various university themed PINK lines.  Not only do they have a different line from campus to campus, but different marketing collateral to go along with it.  I mean they all use the same tools, yet each sign, for example says a different school.

Likewise, other brands have different advertisements from environment to environment, trying to target each market.

Does specializing ones brand automatically put you in the high class category, especially for clothing?  The brands who can not afford to expand, stay local but if they have the money, why is it that the high-class brands tend to be more limited.  You have to go to them, they will not come to you.  What if the roles changed?