[Fish]

You have raised a good point and I think that predisposition probably plays a greator role in so called "stupid crimes" than it does in others. The criminals who cant help but hit every person who makes them mad, or the car theives who don't wear gloves and keep getting caught, etc etc
But I think you are overestimating the risks involved in some crimes and underestimating the thought processes of some criminals.
A marihuana grow is a great example. A person could set up a 500 plant grow in a new community and in one year's time get three harvests and make a profit of one million dollars (after expenses).
The risks they would face are:
Being detected
Being caught and there existing enough evidence to be charged
Being convicted
A hundred little details all need to fall in place (properly) in order to achieve the conviction and then it would probably be only after a second or even third conviction that the person would recieve jail time, and that time would likely be measured in months, not years. Since many of us will work our entire lives and still not earn a million dollars, it would still be profitable even if you were caught and jailed everytime you did it (which would not happen). In a case like this, I believe the criminals' behavior is motivated by very cognitive processes and the "risks" are, to them, just the cost of doing business.

- Chad