One of the things I love about LEGO and the skilled designers that create these amazing sets is their ability to make bricks look fluid and to create movement with unlikely shapes. I feel like tossing loose bricks on top of a build is lazy on their part. I feel as though it's especially a missed opportunity with their Bonsai Tree because Bonsai Trees often have the pebbles and rocks on top glued down. By making them loose, this is less like real life.