Financial instruments are incredibly complex. It's very dangerous to engage with them unless you fully understand what you're getting yourself into. Other people have a huge incentive to exploit any weakness in the financial asset, even in regulated industries. For instance, BlackRock bought credit default swaps in a Spanish company, and then paid that company to default on its debt, thus making a profit at the expense of the counter party. Regulation isn't going to magically make complicated financial instruments safe. People should be aware that they're dangerous and to stay away.