In the first case, you are deploying a SLSB which will have an default implicit no-interface view since it doesn't expose any other business views. Now when you add a @WebService to it, it now explicitly exposes the webservice view which disqualifies it from exposing the default implicit view. If you want the no-interface view too along with the webservice view, then just add a @javax.ejb.LocalBean annotation to that class.
Oh I see, the default behaviour is overrided by @WebService. Thank you !