My characters are beverage drinkers. From Clark Gabrin with his "fine decantation of valuable stimulants and nutrients" designed to taste like an Earl Grey to the national Vardin beverage, sluscheta; to Shelley Huntington's addiction to all things coffee, tea and coffee seems to show up all over in my fiction.
Myself, I am a bit of a tea connoisseur. The family cupboard has always been stuffed to the brim with assorted teas, mostly supplemental or Celestial Seasonings, and my father's pantry contained even more exotic varieties, including coffee alternatives, such as Roma and Pero. When I opened up shop in my own pantry, I included hefty doses of tea for both healing and flavor. An introduction to a local tea room owner led me to fall in love with rooibos as well. So, when my characters began showing personality through their choice of beverage, not only did it not really take me by surprise, but it made for a delightful round table of who likes what and what that says about them.