The Commissioner of Planning and Natural Resources shall make available out of funds in the special “Athletic Fund”, established by section 3010 of this title, funds for expenditures exclusively for sports and recreational activities under the supervision of the Department of Planning and Natural Resources, including expenses for athletic equipment, trophies, travel expenses for insular teams, host expenses for visiting teams, contributions to athletic leagues, teams and individuals, and program improvement and promotion. Provided, that contributions to a league shall be not less than 50 percent of the gate receipts of such league; And provided further, That leagues shall be permitted to operate concessions for refreshments at league games and to retain the proceeds thereof.