We have a tendency to distinguish between chains that sell general merchandise (often wholly corporate owned) and chains that sell other goods and services (often privately owned franchises). In common use, the terms "national stores/chain," regional stores/chain," and "local stores/chain" are aptly descriptive where "stores" denotes general merchandise [incl. specialization] while "chain" connotes either general merchandise; or, other goods (e.g. fast food) and services. So, "high street stores" = "national stores and
[all other] chains." Otherwise, "mall retailers" works. The term "chain stores" [chain as an adjective rather than a noun] covers stores of any distribution size (national, regional, local) selling general merchandise; although, it is occasionally used to generically mean any chain ... which can be confusing even when in context.
