Theres a quite a few reasons why theres so many mopeds outta ohio today. Lets not forget, the industrial revolution, mass manufacturing, innovation of modern luxuries, etc. led to a population boom all happened at in ohio, this led to infrastructure and during the 70's good paying solid middle class jobs. Excess middle class money, established transportation routes, and infrastructure all added to the number of mopeds especially at its height in the late 70's, a confluence of two waves.
Buy why do they still exist? With the movment of production overseas, dwindling resources, and rise of drug use so went the jobs and eventually the people, which left lotsa space. Buildings, Barns, Garages, Basements, Houses, Sheds etc.
People in ohio actually store their mopeds indoors, its not outside like most rustbuckets in cali, it rains rivers, snows a bit (not so much anymore) and the suns pretty hot etc. Also, the economic downturn turned everything into something of value, keep it instead of throwing it away and theres plenty of space.
But most importantly, people also respect their posessions more, say those little things that come with something new should stay with it, a manual, paperwork, or they know whats wrong with it, or what it needs, its history, etc. Its this care for items that has kept the mopeds alive in ohio since it's heyday.