[6][7] In a report, the NRF noted, "multiple offender crimes tend to involve groups or gangs of juveniles who already know each other, which does not earn them the term 'flash mob'.
While often viewed as a form of theft or looting (the illegal taking of items), these crimes more closely fit the definition of robbery because the large crowd creates an implied threat of violence should employees or bystanders attempt to intervene.
Flash robs have occurred in places such as Chicago, Illinois,[9] Portland, Oregon,[10] Houston, Texas,[11] Jacksonville, Florida, Germantown, Maryland,[2][12] Beverly Hills,[13] Los Angeles ,[13] San Francisco,[13] and Walnut Creek, California.
[14][15] As a result of mass flash robberies, shopping malls in Brazil have heavy security, and typically prevent large crowds of young from entering the private property, which has been called a form of soft-apartheid.
[16] In 2013, a rolezinho (strolling) protest movement arose amongst youth, where thousands of young people coordinated their simultaneous entry to normally inaccessible upscale shopping malls.