Starbucks does not compete with local coffee shops, neither with premium chains. They target different markets, serve different needs and got different business models
When do I patronise Starbucks? When I get tired of working from wherever I happen to work from and while on the road. Also I use it as a hangout spots for social and business purposes
Where they have to compete as a proper coffeeshop, they fail miserably (Israel) or struggle big time (Australia)