No person shall become or remain a member unless such person shall use utility services supplied by such cooperative and shall have complied with the terms and conditions in respect to membership contained in the bylaws of such cooperative. However, nothing in this article shall prevent a cooperative from engaging in other lawful activities or enterprises. Should the cooperative acquire any utility facilities already dedicated or devoted to the public use it may, for the purpose of continuing existing service and avoiding hardship, continue to serve the persons served directly from such facilities at the time of such acquisition without requiring that such persons become members. Such nonmember utility service customers shall have the right to become members upon nondiscriminatory terms. The charges for regulated utility services to such nonmembers shall be on a cost basis similar to the charges to members.