Since binaries are now supported in the resources workspace (MGNLRES-38) and that ThemeInstallTask automatically adds images from the theme's /img/ folder in there, why not let it add fonts as well ?

new InstallResourcesTask("/templating-kit/themes/" + themeName + "/fonts/.*", "resources:binary", true).execute(ctx);

As a side note, please update the Javadoc of this class, which still says the contents of /img/ is copied to the dms !