Yeah, and Optimus is a real big rig. It's a disguise!
He's short, merry, and is a complete idiot. Sounds like he's actually a Halfling to me.
Then you don't know halflings.
I know all about Halflings. They're ugly, stupid, merry (which goes along quite well with stupid), drunk, smelly, fat, lazy, useless, and selfish. Why if the world were coming to an end, the Halflings would just be drinking, dancing, and smoking while everyone else actually tried saving it. They're probably too stupid to get in when it's raining, too.
There's the odd exception, one occasionally becomes slightly smart. But that usually drives their little brains into a crazed homicidal rage.