SABMiller - Foster's: The latest froth in a heady M&A environment

    Asahi, a Carlton & United partner and Japan's second-largest brewer, is also reportedly interested in the Foster's brewery; Molson Coors has been spoken of as another possible suitor. Whether any such merger would reward stockholders remains up for debate. Plenty of studies have questioned the benefits of growth through acquisition. Foster's Group admitted as much in May, when it finally announced plans to split its beer and wine divisions after a decade of trying to make those synergies pan out - they didn't.

    Large companies with far-flung operations can also become harder to manage, and beer producers, no matter how large, are still at the mercy of economic realities somewhat beyond their control. While people continue to drink beer in a recession, the most recent economic malaise has shown that the unemployed still drink less - 2 percent and counting in the US. And if the current worries over deflation finally reverse, higher commodity and shipping costs could take a bite out of brewers as well. As Standard & Poors noted recently, brewers' margins have benefitted from the lower aluminum and gas prices that followed the global downturn.

    That said, brewing is certainly not the worst industry for a troubling time, and when stocks aren't riding high in a bull market, it's easier to make expectations and synergies work out as planned. But, as with everything else, investors should probably drink in beer stocks with a dose of moderation.