AverageCommuter

Or if he really needs an analogy outside the realm of transportation, how about the lawn mower analogy. If you've got a yard covered in turf grass then you need to cut it. Whether or not you need a gas powered mower is up for debate. Nonetheless you need to cut it, so you need some type of mower. Now does everyone in the neighborhood NEED to own their own mower? No. Financially as well as environmentally, it makes more sense for a group of neighbors to own one cooperatively and share it. This sort of thing does exist and generally works pretty well. Vehicle sharing (by renting, car-share services, cooperative ownership, even riding public transportation) also makes more environmental and financial sense than everyone needing to own their own. The only reason that you don't see this more often is because government regulations and red tape make it virtually impossible for any group of friends or neighbors to co-own a motorized vehicle.