NEW YORK/LOS ANGELES (Reuters) – McDonald’s Corp’s (MCD.N) announcement that it will raise the average pay at its company-operated U.S. restaurants threatens to complicate an ongoing labor dispute that turns on whether McDonald’s can be held responsible for the labor violations of its franchisees. The decision to hike wages to around $10 an hour will affect only 90,000 of the roughly 750,000 McDonald’s restaurant workers in the United States, because almost 90 percent of McDonald’s restaurants are run by franchisees.