Completely agree with your idea that most people waste their money, I spend most my extra money on books. I read too much. I do disagree with the car payment thing though, you might need a car, and for safety reasons want to get a new one, or you just can't put together enough money to buy an old one upfront.
Well, that of course is a personal preference. If we get down even deeper into the subject, what do we as humans really need? Food, water, shelther, clothing, that's about it! Everything else is a want. We choose to up our standards (Of course, I have more than the 4 things I just mentioned).
For me, car safety comes in paying attention to the road, not texting while driving, not drinking while driving, and hopefully not talking on the phone either. If I were to hit a tree, it doesn't matter what car I'm driving, put simply I lose. If another car hits me, again if its at a high enough speed, it will not matter what I'm driving, I lose.
Also, the last part of your last sentence emphasises one of my points. Let's say I found a cheap car in the newspaper for 2,000 dollars (or even better a friend sold it to me). But I don't have 2,000 dollars. Well, the first thing I need to do is get a job and save money. Most people will say you need a car to get a job. This is only true in maybe 20 percent of cases. I'm sure everyone has a relative or friend that is more than willing to take you to work (My grandmother made the 6 mile round trip 4 days a week for the first 2.5 years that I worked). Even if they are not willing, you can use some of the money you make to pay for their gas, and you are still going to be very much ahead. Once you have saved up about 2,300 dollars start looking for that 2,000 dollar car. It may not be the best car, and it may not happen right away, but it will happen. Also, if possible walking is usually the cheapest alternative and the best one for your body (If you are walking an hour a day, there is no real need for any other exercise), and that is killing two birds with one stone. There are plenty of ways to rework situations such as these in your favor. The real kicker however, is that most people are NOT willing.
The above paragraph was relating to Financial Intellegence.
Something else that I wanted to point out that I forgot earlier.
In order to participate on the forums at Smogon, we all have to have some level of "book" intellegence, because our posts have to have a certain quality. So if anyone thinks they are lacking in "book" intellegence, don't sell yourself short.