We didn't used to dine out often and for the same reason Maria cited. Our kids are older now [12 and 17] so we can justify leaving them at home for a couple hours these days.
My wife and I usually dine out becuase neither of us wants to cook, or we need some adult time to just chat and reaquaint ourselves with each other again. Mostly we go for Italian or California Cusine which offers a kind of eccletic mix of food choices and preparations.
We do, however, always bring a bottle of wine and pay the corkage.....to expensive otherwise