(1) Any hotel or motel licensed under this chapter and under chapter 4 of this title may dispense beer to adult guests through locked, in-room units.
(2) No person under the age of twenty-one (21) shall be issued or supplied with a key by any hotel or motel for such units. Such units may only be located in any such hotel or motel located in municipalities having a population in excess of one hundred thousand (100,000) if the voters of such municipality have approved the consumption of alcoholic beverages on the premises by referendum and in any county in which such municipalities are located if the voters of such county have approved the consumption of alcoholic beverages on the premises by referendum.