Americans making over $100,000 a year are boosting the US economy, with industries ranging from travel and the auto industry to packaged foods and even dollar stores feeling the shift. “Our consumer is a high-end consumer ... They're financially strong. They've got the means. They've got the interest to travel,” Delta Air Lines (DAL) CEO Ed Bastian told Yahoo Finance last week. Its premium business, like Comfort Plus and Delta One cabins, saw revenue increase 9% year over year in the quarter. United Airl ...