I live in flyover country, and rented single family homes here with no problem until we finally bought a year ago. It's true that there's a smaller stock of rentals, but there are more than your example suggests. I'd bet that there are lots of rentals in Westerville, OH that aren't coming up in your search, because they are rented through other mechanisms (anything from Craigslist to a sign in front of the house to locally-specific websites). It's true that fewer people are looking to rent, because buying is more accessible to the median family here than on the coasts, but renting is absolutely a thing that people do.

Also, mortgage is REALLY not the only cost of home ownership. I own a house worth about $200,000. My mortgage payment is about 850/month, my taxes are about 550/month, insurance is 60, and I budget 300/month for maintenance. It would cost me 1600 to rent an equivalent house, so I'm paying more on a monthly basis to own than I would to rent. Some of that is equity, true, which is why we bought. On the other hand, when/if we sell, we'll be paying a realtor $12,000 for the privilege, so we'll have to live here awhile before the equity gains outweigh the transaction costs.