please see first reply by George Seese at the end of this tutorial: http://code.makery.ch/java/javafx-8-tutorial-part4/

"Another feature lost in Scenebuilder 2.0.

When adding a stylesheet on each fxml file, the "Add Style Sheet" dialog starts with \Computer.
In 1.1, it finds the css files in view package.."

why should this be fixed?

Programmer-Convenience or ease-of-use, which affects the overall view of the professionalism (or sophistication) of SceneBuilder as a serious development tool that other programmers would actually push on their friends/coworkers.