McDonald’s and its roughly 3,000 U.S. franchisees are fighting to break a long streak of lackluster sales that has made it virtually impossible to boost prices on its famous hamburgers and french fries to cover higher labor costs. McDonald’s declined comment. McDonald’s Corp says it can increase pay only in the small number of restaurants it operates. Wal-Mart on Thursday said it would increase entry-level pay to $9 an hour, a move it estimated would cost $1 billion and affect some 500,000 employees.