I count everything. Maybe not salt and pepper

but, when I'm calculating a recipe, I also count tsp's of dried spices even.
Partly because something low calorie might still add up to a lot if I eat a lot (as punkrprincessa says), partly because some veggies can be quite high cal, and certainly high carb (as rainbowstripe says); mostly because it would feel like cheating to me if I didn't, and if I cheat on lettuce, it's only a couple of steps to cheating on sugar or cheese or meat.
Mnot saying it Is cheating, just saying how it would affect me.