Yes, but it is very symbolic - in ceremony, you drink wine and eat bread, which is probably how Christianity got it in the first place. It's the most basic of food, symbolically. When you've had it, you tuck into the full meal.

Climate and theology, yes! :-) Agreed, an interesting idea. As I have heard, in England in later times, anyway, most people would drink ale, then beer when it became the drink of choice(you had to make ale daily, while beer kept better, according to a history of drinking in England I have read). Wine would indeed have been posh, I imagine.