It sure is keeping salaries lower, how much are you willing to pay for a Big Mac. How much for a night's stay in Motel 6? How much for clean restrooms? That's the point. It'll all cost more, which doesn't mean it shouldn't happen. It will also take time to raise all those salaries for our children (who presumabely want these jobs) without throwing all these businesses into the red.
You make an excellent point. Paying higher wages means higher costs for everything, resulting in those who got the higher wages not gaining any ground and everyone else loses ground, especially the elderly on fixed incomes.