Monopolistic practices and driving out local business is unethical corporate behavior. I agree, if Starbucks is engaging in such activities they should be properly regulated. However I would like to voice an alternative opinion - Starbucks isn't all bad.
Diversity
Starbucks *can* (and I would argure that it *will*) diversify itself in other cultures because their goal is to create an inviting atmosphere that encourages people to buy coffee and come back, and if a different atmosphere in Saudi Arabia promotes that, then they should diversify. Also, local branches will still be operated by local workers.
A claim such as "Starbucks has no incentive to innovate on their menu or their décor" seems to have no backing. I can think of a major incentive to innovate and alter decor - PROFITS. In areas that are notably anti-American, Starbucks would do well to change their decor or menu items in order to encourage people to spend money in their stores.
As an example of this Ouroboros suggests I "might wish to offer the example of McDonald's, which adapts to its local market, for example, in Hawaii, they offer a variety of somen (noodle) soups."
Competition
The idea behind capitalism is competition. If Starbucks does really well and starts really pulling in a lot of money, there is no reason why a similar sized competitor cannot take some of Starbuck's market share.
I would argue that Starbucks *does* have a superior product, at least compared to several local coffee shops in my area. American coffee shops focus on "American" coffee (drip coffee) and not the espresso drinks that Starbucks is known for. Their innovation in this area opened up market share by exposing more people to drinking coffee.
Bias
Lastly, terms such as "economic American Imperialism" give the false impression that the US government is maliciously seeking to impose Starbucks on all other cultures in order to benefit ourselves. Open market is just that, open. The same system that allows for Starbucks to open up a store in India allows for an Indian programmer to take an American programmer's job.
The claim that Starbucks is inherently "American" is unclear. Why can't the company be more Italian than American, for example. There are American businesses that have an anti-American culture. When Starbucks first emerged they specialized in a type of beverage that was not mainstream for Americans. The repeated use of the word "American" is simply there to galvanize anti-American sentiment. They are an American company and some profits go back to America however Starbucks also contributes to local communities.