Well, say it is insider trading. Why is that so bad?
Suppose you are working in a law firm, and you know that a company who is your client is going to merge with another company, so you buy up the stock of that other company? You would go to jail for that–but does it seem so bad.
Meanwhile, if you were the waitress who overheard them talking about it and you went and bought up the stock, it would not be a crime at all.
Does that make sense that one you go to jail and one is no crime? Are your morals really based on that distinction?