Yes, this is something that makes cycle-touring what it is for many people -- appreciating the fact that small towns do exist off the interstate highways. They can be interesting to explore, and sometimes there are parallel roads that the interstater replaced that have almost no traffic on them because their only function now is as service roads.

I always sympathised with the frustration. verging on desperation. of the people in small towns when faced with the authorities building interstate highways that bypassed them. The Hume Highway, which connects Melbourne and Sydney, is a classic example because it has numerous small towns off it that struggle to survive whereas when the highway ran through those towns, they were relatively vibrant and interesting.

So the message here is... be aware that not all dots on your maps represent existing habitation with services; they may well be ghost towns doomed 20 or 30 years ago by construction of an interstate highway five or 10 miles away.