Steps to recreate:
1.) Start with a fresh 6.2.0 M6 Bundle
2.) Click Action > Manage for the Global Site.
3.) Click Application Display Templates.
The out of the box sample ADT's are not appearing in the list.
They are still usable from the portlets. For instance if you configure an Asset Publisher and go to Display Settings and drop down the Display Template's you will see Rich Summary listed under Global.