(1) Every motor carrier as defined within the Montana Motor Carrier Act ( 69-12-101, MCA) is deemed to be in the business of transporting people or property for hire on a commercial basis upon the public highways of the state of Montana. Any business venture or business transaction inconsistent with the status of the carrier as providing common or contract carriage, is deemed not within the interest of providing and maintaining a public transportation system and is hereby prohibited. Such business ventures or transactions include transportation movements of private carriage, so-called "buy and sell" agreements, or operating under so-called "brokerage agreements," and are therefore prohibited.