Up to 50% of the parking spaces for bowling alleys, theaters, auditoriums or private clubs and up to 100% of the parking spaces required for churches or meeting halls may be provided collectively and used jointly by banks, offices, retail stores, repair shops, service establishments and similar uses not normally open, used or operated during the same hours as bowling alleys, theaters, auditoriums or private clubs, churches or meeting halls; provided, however, that a written agreement assuring the continued availability of such parking areas shall be properly drawn and executed by the Borough Solicitor and filed with the application for the zoning permit.