re: frontage

as an expansion on the american english dialect questions from yesterday, i'm wondering if 'frontage' is a common word, in general, wherever people tend to say 'frontage road' for the road that runs parallel along a highway.

it seemed like people who didn't have a lot of these roads around their highways seemed more likely to call them 'frontage roads' (if anything) and that seems strange to me since frontage isn't a word i have ever used, and if something was uncommon, i would think the term would have a more common phrasing, like 'side road' or something, if not one of the other terms like access and service.

so yeah, i'm wondering a- if you have a word for this but the roads themselves are uncommon, do you say frontage road or something else? and i'm wondering if that is the case, do you say 'frontage' in other contexts?