What was the secret of Coors Beer's prosperity before 1970s?

The secret of Coors beer's prosperity before 1970s was that the beer was brewed with pure water with good quality. Coors beer is brewed with pure rocky mountain spring water, with excellent quality and light and palatable taste. This kind of beer is produced by only one company, mainly sold to sparsely populated areas in the United States, and the benefits come from Coors beer of famous and unknown people.