I guess even dumb as they are, they know no one will stop them.

A small city on Colombia's Caribbean shore is being crowded with migrants from Haiti, Africa and Cuba making what they hope will be a journey toward the United States.Local official estimate more than 10,000 migrants have massed recently in Necocli, a city of some 20,000 people better known for its beaches, coconuts and burbling mud volcanos. It has become a bottleneck on the global migrant trail that winds through South and Central America, and on to Mexico and then the U.S. southern border.
https://ca.news.yahoo.com/colombia-c...040445443.html