It is declared to be the purpose of the general assembly in the passage of this part 5 that in connection with the construction, maintenance, and supervision of the public highways of this state, the state of Colorado place itself in a position to receive its full share of funds to be apportioned by the congress of the United States for expenditures on federal-aid highways in this state and, to this end, to control the existing and future use and maintenance of junkyards in areas adjacent to the interstate and primary highway systems in order to protect the public investment in such highways; to promote the safety and recreational value of public travel; to promote public pride and public spirit, both on a statewide and local basis; to attract to this state tourists and other travelers with a view toward broadening the economic well-being and general welfare; and to preserve and enhance the natural and scenic beauty of this state.