Why don't the rich sports team owners and players build shoe factories in the USA?

Why do the rich basketball players, baseball players, football players, hockey players, golfers ect in the United States endorse the products made outside their own country rather than get behind products made here or build factories to make shoes and clothes here? The name of "J*rdan" will sell any thing but where are the shoes and under-ware made? The name "G*orge For*man" is on stuff made in China. Please correct me if I am mistaken.