This subtitle does not:
(1) Diminish any authority of Anne Arundel County, Howard County, or a municipal corporation to license and regulate mobile seafood vendors;
(2) Apply to charitable or nonprofit vendors who sell seafood at short-term festivals or other short-term events;
(3) Apply in Calvert County and in St. Mary’s County for those persons selling their own seafood catch; or
(4) Diminish the authority of a county to license and regulate mobile produce vendors.