This explain the sad Batman. In actually, it's not Sad Batman, but Mad Batman.
Kidding aside, I'm in the impression that they borrowed a bit from the Omac project, where Superman gets mind controlled? That's probably the reason why Superman was going on a rampage that incurred Mad Batman's wrath. So is Maxwell Lord in the movie? Will we see some neck twisting from the Amazon princess?
You know, I like the sound of Mad Batman better. "I'm the Goddamn Mad Batman!!!!"