Criminals who get caught do more or less the same things that ordinary citizens do, because the systems setup to catch them assume they'll act like a normal person, because you catch the greatest number of criminals that way. By definition, we have no information about what criminals who don't get caught do, because they're never identified as criminals. That's the point.
Selection bias is the most powerful force in the universe.
Reminds me of the Stainless Steel Rat, where he is intentionally caught and sent to prison, hoping to further his criminal education. Only to find out he is now incarcerated with all the criminals that weren't smart enough to evade capture...
This is essentially Pareto resource efficiency for crime. Spending 20% of resources catches 80% of criminals. To catch the other 20% you have to spend exponentially more with exponentially diminishing returns. (This model is too simple though as the environment isn't static and criminals are able to learn and adopt strategies that make your efficiency decay over time)
Selection bias is the most powerful force in the universe.