I would say the decision was more motivated by the target market than, "breakdancing simply isn't making enough money." The sports added (outside of cricket, which was added for a different target market obviously) already exist on the American market. Breaking doesn't have the same reach in the United States as American football or lacrosse. As @Laraja noted, the WDSF had to establish an international calendar and formalize the format across competitions. Like any sport, breaking could tap into the American market at some point, but it represents a greater unknown than the chosen six sports.