Md. Code, Business Regulation § 20–102

(a) This title does not apply to an automated purchasing machine that is used exclusively for collecting recyclable materials in accordance with a recycling program approved by the Department of the Environment.

(b) (1) Except as provided in paragraph (2) of this subsection, this title:

(i) preempts the right of a county or municipality to regulate automated purchasing machines and operators of automated purchasing machines; and

(ii) supersedes any existing law of a county or municipality that regulates automated purchasing machines and operators of automated purchasing machines.

(2) This title does not limit the power of a county or municipality to:

(i) license automated purchasing machines and operators of automated purchasing machines; or

(ii) prohibit the installation or operation of automated purchasing machines within the county or municipality.