The libraries can be prepared the way the surfaces are made inside the object, not trashing the attributes in the project. Maybe the creator of the library did not know how to do it/ or the producer wanted it this way. If I were about to prepare such library I would strongly persuade the producer not to do that anyway.
There is no good way of removing the unwanted attributes (automatically).
Looking at the picture I can see the library contains a "master_gdl" file which forced the import of the surfaces.
(if the names of the surfaces are italic - it is the sign that they came from such file)
So you can avoid loading all the surfaces by removing the master_gdl file from the library before loading it...however the objects can either no longer work as designed or not work at all. Maybe when loading the needed surfaces from the "contaminated" file could solve some of the problems above.
Best Regards,
Piotr