It's better to see something once, than to hear about a thousand times.
One of the biggest eye openers for me in the past few years has been the idea of travel hacking. I had my first credit card when I was a senior in college. It had a $500 credit limit. A few months later, I was already maxing out that limit. I had no concept of credit (despite majoring in Econ), let alone how to use it wisely. Fast forward a few more years, I got into more credit card debt. Thankfully, I was able to put a stop into my credit card debt and started getting wise about its use.