I used to work in risk management at an investment bank. When things went wrong, and the result was a gain, we incorporated it into our models as if it was a loss of the same magnitude.
If you be once and win you then can roll the money into lower return legitimate enterprises and sail off into the sunset.
I'd wager that most businesses that start as a single person doing something (be it investing money or detailing cars) start as off the books, under the table, zero regard for regulatory compliance type businesses. It's only when they've made enough on that initial investment outside the rules that they turn around and incur the cost of compliance.