SUMMON THE idea of the German at play, and chances are you see a rosy-cheeked Lederhosen- or Dirndl-clad youngster bearing half a dozen overflowing steins of beer. Never mind that—as the rest of Germany will hasten to remind you—you have taken Bavaria as a synecdoche for the entire country. The real problem with this image is that Germans are losing their taste for the tipple that once defined them.