They're indestructible and they're everywhere!
I'm sure you all remember this scene from the 1986 Transformers: The Movie which introduces an army of mounted Junkions charging to battle riding one another.
While other Deluxe class Transformers can ride transformed Wreck-Gars, only Wreck-Gar is actually made to ride another Wreck-Gar. Wreck Gar comes withe multiple pegs - most notably those in his groin area - which allow him to better attach to another Wreck-Gar in motorcycle mode. He has another peg on his left leg that also attaches to the bike and a recess on his right leg that attaches to a peg on the bike. Any of these attachments allow for a solid mount for Wreck-Gar on a transformed Wreck-Gar which allows for quite a lot of memorable poses.
I can absolutely guarantee that collectors world-wide will start taking liberties with Wreck-Gar to made unique Junkions to follow the charge of their liege-lord Wreck-Gar.