Specialty bikes, utility bikes and cargo bikes are for the rider who wants a bicycle that is outside the norm and can deliver tasks that are usually not met of a regular bike.
For example they want to carry a lot of stuff while on the bike or take a friend, a kid or the spouse to ride together. Or they would like to ride a 3 wheeler trike to the grocery store or haul their belongings around the globe. There are many different specialty bikes around like tricycles, trikes, box bikes, utility bikes, tandems, all terrain "Fat" bikes and more.
Bike Attack in Santa Monica carries Utility Bikes and Speciality bikes from many brands, like Surly, Virtue, Babboe, Gazelle, Norco, KHS, Sun and Torker.