I drive through Indiana several times a year, going to Michigan, most recently in November. I've not encountered any sort of perversity related to RVs or out of state drivers. If you are seeing RVs at scales, those are commercial movements, and they have to follow commercial rules in every state. Several hundred a day coming out of north central and northeast Indiana.
Maybe a neighboring state slander? Maybe Indiana folks tell each other to stay out of Ohio because they enforce speed limits.