It shall be unlawful for any person to obstruct, encroach upon, solicit the sale of any merchandise on, or injure materially any part of any public road, and any person who unlawfully obstructs, encroaches upon, or injures said public road shall be responsible for reimbursing the Department of Transportation for the costs of removal of said obstructions or encroachments and the costs of repairs to the public road, including any costs associated with traffic management; provided, however, that such costs shall be limited to those costs which are directly incurred from such damages. Costs incurred for traffic management may include, but not be limited to, costs incurred for flagging, signing, or provision of detours, provided that these activities are directly caused by the obstruction, encroachment, or injury to the public road system. However, nothing in this Code section shall abridge or limit any authority provided by law for the installation and operation of vending machines at welcome centers, tourist centers, and safety rest areas. Nothing in this Code section shall limit in any way the department's authority to lease property to state or federal agencies, counties, or municipalities as provided for in Code Section 32-7-5, or limit the Department of Transportation's ability to grant a license to any utility or railroad corporation as defined in Code Section 46-1-1.