Where I live (and in many parts of London) there are speed humps every 50-100 yards so unless you drive at 10mph you risk bottoming out a car with a lower ground clearance. Also, parking is an absolute nightmare (very little off street parking) so a shorter car is more practical to squeeze into parking spaces. As a family of 5 with a dog, we considered an estate but decided a shorter, taller car makes far more sense for us.
I agree that width of cars is important though, some of them are becoming ridiculous now, perhaps to accommodate the increasing obesity of the occupants!