The be yourself moral is something Nostalgia chick once talked about- and both Disney and Dreamworks use it, the difference being is that Dreamworks wasn’t always for perfectly bodied young people in that area. XD.
IDK, it just does kind of conflict with the first movie in many ways too.
I think the thing is, that sometimes in life you don’t always necessarily hurt peoples feelings or insult them through being malicious or selfish. Ignorance can also cause that to happen too. And while Mater is knowledgeable of car parts and all he doesn’t it seems really understand on a subconcious level as Lightning implied, that life doesn’t work like Radiator Springs everywhere else. And well, if your ignorance causes you to insult people or hurt their feelings then you should work against it. Granted, Mater never seemed to realise he MIGHT have insulted certain cultures (if once again the Cars cultures were exactly like our own).
Personally, I think Mater should have encountered some form of culture shock when he separated from Lightning. It’s a real phenomenon, that when you are thrust into new areas without the support system of your loved ones it can be distressing. Add to the fact Mater does not seem to precisely understand other cultures and it would probably increased.
Also generally speaking movies have the main character learn something and change in some way for the better. I mean conflict can come from both the outside and inside. I’d have liked it if Mater had got interested in other cultures and wanted to read up on that stuff among other things.
The story about alternative fuel in their world was… odd to say the least. It mostly seemed in my view was that ‘Big Oil companies can’t be trusted. The end.’ And the plot was a little convoluted because as I mentioned in my review, we never got the real impressive alternative fuels were a big deal in the Cars universe and a real threat to oil’s influence (as in there were other companies promoting alternative fuel a lot). And well, as I said, alternative fuel isn’t even always green anyway. And TBH, the ‘once big oil always big oil’ made me also raise an eyebrow too. I mean people CAN change you know. Like… your friend Lightning? Anyone?
Are we pretending Lightning never was kind of a jerk and changed? Okay then.
I mean oil companies are hardly angels in our world, and pretty corrupt in many ways. They also have a lot of influence on politics and thus alot of power, far more than they should have.
But I think this was also a problem with the movie- you can’t necessarily assume the audience will accept the Cars world is completely our world just with cars, or to even know about these things (especially kids!). I mean yes in OUR world major companies involved with oil have a lot of power and political influence but you have to establish that in the movie too- even if you are showing car versions of the Queen and exact replicas of areas in our world in the movie. A movie which relies a bit too much on outside knowledge and the audience making certain assumptions on the Cars world to entirely held together neatly in the end.
I mean I love the friendship between both an army car and a hippie but the fact they ‘knew’ was a little… eh. (OTOH with Sarge, wars have been fought over resources and powerful people thinking themselves as more important than others lives rather than say something meaningful or right too… but like I said, it’s not really neat and they really, really should have established it in the Cars universe itself as having happened.)
The most problematic thing is that the lemon’s problems were never resolved in the end to me. I mean with stopping their parts it would be like someone had these specific medical requirements to function and the rest of the world went “lol no. No point in doing this anymore because you’re useless and a joke and a burden to us all” and stopped the treatments entirely. Or stopped a certain type of organ donation perhaps.
Even if I wasn’t one of them I’d be rather horrified at such a thing happening.
Also it’s kind of odd that the Cars world would completely define a Cars worth entirely in their mechanics. I mean clearly, while convoluted in the story, their plan could have worked. They’re not really stupid. Therefore, while in our world, they are just useless machines with no mind of their own (and cars don’t have minds or thought or feelings in our world)… in the Cars world that’s hardly true. They can think/feel or whatever. So they can still make contributions to their society in some way. And even if they couldn’t, sentencing Cars to a slow ‘death’, well that’s pretty cold.
This movie can be alot of fun don’t get me wrong (it has great action, and I liked Finn and Holly) but there are some unfortunate implications here and there as well as relying on the viewer knowing/assuming certain things for the entire story to work.
I like to leave the theatre with some morals and such to consider, not the glaringly obvious kind but things to keep in mind. I got those feelings from Cars, but Cars 2 left me wondering. “Always be yourself” seems like a lame moral to draw from Cars 2, not that it is a bad moral, but it could have been presented much better. 
