It is against the law to stand around any building without a good reason.
609.725 Vagrancy. Any of the following are vagrants and are guilty of a misdemeanor: (1) A person, with ability to work, who is without lawful means of support, does not seek employment, and is not under 18 years of age; or (2) A person found in or loitering near any structure, vehicle, or private grounds…