Continuity mistake: In the scene where the Autobots are escaping from the KSI building, closely pursued by Galvatron and Stinger, the satellite tracker used by Joshua to track them, using an orange false image view, indicates they are driving on a freeway leaving the city. This is backed up by a swooping shot showing the same. However a second or two later and they are in the middle of an open countryside, not a building in sight (there are many 360 degree camera sweeps), a few bridges and other cars, but also old concrete banked curves. This is on a test track which for some reason they didn't CGI to make it fit with the supposed scenery the satellite indicated they were near.
Continuity mistake: In the scene where Cade, Shane, Tessa and Lucas are running away from Lockdown, they leave Shane's car behind. After Lockdown's grenade detonates, the car is nowhere to be found in the aftermath.
Continuity mistake: At the end you see Bumblebee driving in and in the far away shot you see him drift/stop in front of Cade and everyone but next shot you see him drive in again and transform.
Continuity mistake: As Shane is driving to escape the Black Ops cars, he drives through a chain link fence with a private property sign on it. A second later, he hits it again.
Chosen answer: The battle that lead the government to hunting all transformers was in Chicago, but the incident that took Optimus out of commission was not. He'd been on the run for however long, even changing his appearance to avoid detection, when he was ambushed. Wounded, he snuck into the theater to hide before transforming one last time into vehicle form at which point he basically passed out, lost consciousness, or whatever it is robots call it when they involuntarily shut down (stasis). His aggressive reaction upon waking is simply down to his instinctive warrior reflexes immediately kicking in. All humans are a potential threat to him now, so he reacted accordingly in an instant.
Phixius ★