American trade unions have boycotted consumer products of big employers. More and more mass protests are organized by middle-class zealots supporting complicated and divisive issues like abortion, experiments on animals, the environment or political repression in foreign countries. Campaigns have been organized, for example, to stop canners selling tuna fish caught in nets that also trap and kill dolphins, against hamburger chain importing beef from ranches that had destroyed tropical rainforests, against companies experimenting on animals and against wearing fur coats.