I always wonder who the hell buys bagged, prechopped salad. Assume it's people with more money than sense. 
I am fairly fond of the kale and cranberry salad they sell out of the Costco, but yeah... otherwise, I put em together... lots of Romain, Spinach, tons of veggies, and not a little forage. And since a lot of my summer veggies are canned by way of fermenting, there's a strong vinegar component, which is nearly always augmented by some sort of vinaigrette style of dressing.