“Frontage” is the nomenclature I usually see in lieu of “feeder”. Though I agree that feeder is more descriptive of what the road actually does when we consider a road as being as a network or graph with flow.
Though the roads you reference would probably not be called “feeders” in the same way. I take feeder specifically in the Houstonian meaning to refer to a frontage road that is used for local access that runs parallel to a limited access highway. Notably it must run parallel to the highway and exist for the primary purpose of providing local ingress and egress while preserving the limited access nature of the highway.
Though the roads you reference would probably not be called “feeders” in the same way. I take feeder specifically in the Houstonian meaning to refer to a frontage road that is used for local access that runs parallel to a limited access highway. Notably it must run parallel to the highway and exist for the primary purpose of providing local ingress and egress while preserving the limited access nature of the highway.