It seems like big-time mergers and acquisitions are everywhere these days. In the beer world, Anheuser-Busch (Budweiser, etc.) is buying SABMiller (Miller Lite, etc.). American Airlines and US Airways merging. And now, two major pharmacy chains will join forces to compete with CVS Health, leaving us two major choices in the drugstore world. What does the Walgreens-Rite Aid deal mean for us as consumers?