Indeed, the old exclusionary mentality of craft-based unions remains strong. Even for industrial unions that went beyond craft-ideology, there is no automatic step from unionization to working-class solidarity that goes beyond immediate group-interest & national boundaries. For this reason, Lenin polemicized against the Economists' slavish worship of "spontaneity." He wrote: "The history of all countries shows that the working class, exclusively by its own effort, is able to develop only trade union consciousness, i.e. the conviction that it is necessary to combine in unions, fight the employers, and strive to compel the government to pass necessary labour legislation, etc." One wishes Lenin had been wrong, but so far the history of capitalism -- especially in the West -- has borne out his criticism of the limits of economism & trade union consciousness. Nowadays, even many anarchists have given up upon anarcho-syndicalism & gone for a kind of anarcho-primitivism.
That said, it's still better to be organized than unorganized.
Yoshie