yeah, folders serve us well for bart trips, and for getting/returning a rental car, and even for going somewhere where you know you'll be getting a car ride on the way back (or on the way somewhere else) and you can just stick the bike in the trunk.
also, it's the easiest bike to carry on our bike trailer, so it's the trick for getting a bike to the shop for repairs, or going to meet someone at the train and bringing a bike for them to ride. And, it's a handy guest bike since it's adjustable to fit most adults.