Getting a new car most often is about ones
EGO, as in to say:
I've made it,
I worth it,
I deserve it,
I'm compensating for my inadequacies
or even better the need to just buy stuff which WE ALL have.
Americans are most known for being CONSUMERS,
not hard working,
ethical,
dependent,
loyal,
smart (HAHA),
or anything else but consumers and our purchases are almost always not out of necessity. Not to mention that more then 33% of what you buy is thrown out instantly. I speaking of the packaging.
Look around as you drive, in my home town, I'm driving the oldest crappiest looking car I see most every day.
I had a flawless 98' Buick Regal GS loaded with every option, it was a kings car (literally Regal), but the mpg sucked. I paid $2800 for my Hx meaning it'll take just about 2 years to have the car pay for it's self.
The Buick got 19 MPG
The Hx is currently at 36.
Lastly, as Zonker stated keeping your old car is the green thing to do.
Unless it's a Nissan leaf