From April through October, I race a 37-foot sailboat every Thursday night. The course changes weekly, and ranges from three to seven miles long, depending on the wind.

Before the race, we review the course and weather conditions and decide our strategy for the starting line. During the race, we generally enjoy the sail and competition, with only the occasional bout of yelling. We also enjoy a good beer, while on the boat and afterwards when we retire to the local Irish pub.

Some of the crew order the same brew every time, while others are always trying something new. As I looked down the row of taps, it struck me that while the beers might taste different, many are owned by the same company.

And it’s about to get worse.

In a deal worth more than $100 billion, two mega-brewers, InBev (BUD) and SABMiller (SBMRY), are merging. The companies control 45% and 20% of the U.S. beer market respectively, offering more than 350 brands.

In addition to category kings like Budweiser and Miller Lite, they own Goose Island, Corona, Landshark, and 10 Barrel Brewing. While InBev is bigger in the U.S. market, SABMiller has some of the better names, including Australian brews Fat Yak and Dirty Granny.

After more than a decade of consolidation in the beer market, this merger seems like the culmination.

As fast as micro-brews open – and they open every week – big players snap them up. Without additional markets to exploit, or more drinkers buying beer, the entire game boils down to stealing market share from competitors. To grow, the logical path is to buy them out.

In general, mergers and acquisitions have to make financial sense. Perhaps one company is much stronger than another and can produce goods more efficiently.

But more often than not, the acquiring company is simply buying growth instead of creating it because opportunities are limited.

And with low interest rates and high stock prices, it’s been easy.

Using debt issued at a cheap interest cost, highly valued shares of the company’s stock, idle cash, or a combination of the three, the purchaser can vacuum up market share without going through the hard process of expanding organic sales.