Just saw this posted by the city on another post - looks like they are eligible for a fine for up to $100 per day :

Sec. 18-25. - Posting notices, etc., on property without permission.

No person shall post up, or affix in any manner, any bill, placard, advertisement or notice, either written or printed, upon any fence, traffic control signal, litter receptacle, bridge, wall, post, pole or upon any part of any building in said city, without the previous consent of the occupants thereof; or, if there be no occupants, without the previous consent of the owners, thereof; nor upon any building, sidewalk, curbstone, tree, fence, or post belonging to said city without consent of the director of the department of public works, nor upon any pole belonging to any telegraph, telephone or electric lighting company, without the previous consent of such company. Every person who shall violate any of the provisions of this section shall be guilty of a misdemeanor and upon conviction shall be punished by a fine of not more than one hundred dollars ($100.00) for each day that the violation shall continue and shall be required to abate the violation.

(Code 1928, § 994; Ord. of 10-17-88, § 12)

Cross reference— Enforcement of § 18-25 by civil officers, § 32-2.