Ethnic groups will always extort their own community. Chinese extort Chinese businesses, Albanians extort Albanian businesses, Russians extort Russian businesses, African-Americans extort African-American businesses,etc... Extorting a business out of one's own community is suicide. The power of the American Mafia are the labor unions. Outside of these rackets, they also only extort Italian-run businesses.
you're right, that's why i think italian mafia is more involved in extortions since italian businessmen in new york are probably much more than other groups prone to extortion like russian or chinese
