Vehicles inactive and non-talking vehicles

OK, I watched the movie for the second time and noticed 2 things:
None of the bots or cons ever talk when they are in vehicle mode. Why not? It would be sort of silly if they needed to transform to talk. I mean, why didn't Barricade try interrogating Sam about the glasses when he was a police car, or why didn't the Autobots talk a little while they were cruising down the roads?
Why did the autobots just SIT AROUND in car mode? I can totally understand inactivity if they are disguised as a car, like bumblebee was for much of the movie... But at times it was just ridiculous. During the final battle, Just after Bumblebee had his legs blown off, there were several shots of Jazz just PARKED. He wasnt fighting, or driving anywhere or even expressing concern for Bumblebee. He was just SITTING THERE until Sam said "MOVE OUT OF THE WAY" or something and he finally backed up. Next time you see the movie check out this odd scene.
Also, the final scene with the autobots all sitting on a hill in vehicle mode, except optimus. WHEN do transformers ever just sit around in their alt modes? I cant think of any time in the comics or cartoons that they just sit around PARKED UNLESS they are "under cover"... If Optimus was a robot in that scene, I see no reason his men would have been just sitting around as cars.
None of the bots or cons ever talk when they are in vehicle mode. Why not? It would be sort of silly if they needed to transform to talk. I mean, why didn't Barricade try interrogating Sam about the glasses when he was a police car, or why didn't the Autobots talk a little while they were cruising down the roads?
Why did the autobots just SIT AROUND in car mode? I can totally understand inactivity if they are disguised as a car, like bumblebee was for much of the movie... But at times it was just ridiculous. During the final battle, Just after Bumblebee had his legs blown off, there were several shots of Jazz just PARKED. He wasnt fighting, or driving anywhere or even expressing concern for Bumblebee. He was just SITTING THERE until Sam said "MOVE OUT OF THE WAY" or something and he finally backed up. Next time you see the movie check out this odd scene.
Also, the final scene with the autobots all sitting on a hill in vehicle mode, except optimus. WHEN do transformers ever just sit around in their alt modes? I cant think of any time in the comics or cartoons that they just sit around PARKED UNLESS they are "under cover"... If Optimus was a robot in that scene, I see no reason his men would have been just sitting around as cars.