On the rear left bumper of my xb, there is a small spot, about 3" X 2", that looks like you can pop out the plastic, and stick something there. What option/accessory is this for?

It is for a threaded tow hook that can be screwed into the bumper. It is on the front of some vehicles also, including the Prius.

There is also a piece in the front, in the lower grill. The same on the xA.

They shouldn't have done that. Who is actually gonna tow something with a Scion? And, since I'll never tow anything in my "baby", now I'm stuck with an ugly "cut out" box on my bumper...

Thanks for the info, guys :D

They are tie down spots for when the cars are shipped. EVERY imported car has those. Try not to think about it...

http://www.scionlife.com/forums/viewtopic.php?t=10129&highlight=tow+hook