A $20.1 billion merger of beer conglomerates is now delayed, after the U.S. Justice Department sued to stop Anheuser-Busch InBev’s acquisition of Mexico’s dominant brewer, Grupo Modelo, Thursday. The agency’s antitrust division says the two corporations haven’t done enough to protect consumers.

The deal would put Corona, Bud Light, Stella Artois, and other popular beers under the same corporate umbrella. The Mexican government approved the merger last November.

In its proposed form, the merger “would result in less competition and higher beer prices for American consumers,” says Bill Baer, Assistant Attorney General, of the Antitrust Division. “If ABI fully owned and controlled Modelo, ABI would be able to increase beer prices to American consumers. This lawsuit seeks to prevent ABI from eliminating Modelo as an important competitive force in the beer industry.”

According Bloomberg News, Modelo’s and AB InBev’s pricing strategies are diametrically opposed, with Modelo consistently providing pressure for lower prices, in contrast with “ABI’s well-established practice of leading prices upward.”

READ Bloomberg News on more about the suit.

As a microbrew drinker, of course I am happy about the decision. Let’s look at what is occurring now in Mexico.

Over the years, small regional breweries have been swallowed up in Mexico. Now a duopoly controls 90 per cent of the market – Modelo on the one hand and, on the other, Cuauhtemoc-Moctezuma, which Heineken acquired a couple of years ago. What remains of the domestically owned beer industry is a small batch of craft breweries at just 10% of the market. Even an established international giant of the industry, London-based SABMiller, has complained twice now to Mexico’s anti-trust authorities about its inability to pierce the Mexican market.

Outsiders such as the craft breweries and SABMiller can place a handful of their products in some supermarkets and upscale restaurants. But the core market for the nation’s brewers lies in tens of thousands of bars and cantinas throughout the nation. You can have either a Dos Equis, Heineken’s leading Mexican brand, or a Corona, brewed by Modelo, but you can’t choose one or the other in the same cantina.

When InBev took over the German import Beck’s, it moved the production of the lager from Germany to the United States and it made changes to the recipe to lower production costs. When you hone down the brewing process so it costs less to produce the same beverage, it has consequences, i.e., less flavor and less body.

Even though we are in the same situation as Mexican beer drinkers, already the U.S. market is essentially a duopoly. SABMiller controls 26 percent of the US market. Anheuser-Busch InBev currently has 39 percent of U.S. beer sales. If it acquires Groupo Modelo, it would jump to 46 percent.

Amongst all of this, both SABMiller and InBev are on buying sprees and there is a good chance that your favorite beer is “crafty” and not a craft beer. Here is a great article on the craft vs. crafty beer wars and some microbrewers who are working hard to keep our choices plentiful.

And another article from Time about the fight over craft and crafty brewers.