Updated Oct 27
Read the original “Freakonomics” book. The authors encountered a street gang which had kept detailed records of money earned by each member. The last-step, standing-on-the-corner type drug dealers were earning very little, and some even had other jobs, such as fast food.
Selling drugs requires having a wholesale connection, who may be rather aggressive. It also often involves gang association. So you cannot just set up your own independent operation.
That level also has a high risk of violence from rivals (including in their own gang), and from desperate addicts, along with a high risk of arrest.
Have you ever interacted with someone who was desperate for heroin or cocaine, and who didn’t have any money? It isn’t fun.
Illegally selling guns means that you need to obtain them from an illegal source, such as burglaries. And your customers will be the types of people who illegally buy and use guns.
At whatever level and type of crime, you will be surrounded by other criminals, possibly including those with zero hesitation to initiate violence. Sometimes just because they are in a bad mood today. They may be rather agitated with their own fear of arrest. And drug use leads to all kinds of irrationality. You cannot exactly call the police to report that someone robbed you or attacked you while you were doing something illegal.
A lot of crime requires openly or semi-openly doing illegal things in public spaces, or in private spaces that aren’t yours, interacting with strangers or very superficial acquaintances.
If you are robbing convenience stores, the owner may have a gun behind the counter.
Armed robbery of banks is glamourised in media, but has a very poor risk/reward ratio, in terms of physical danger and prison time vs the amount of cash in a teller’s drawer.
A lot of crime (especially with close proximity to violence and drugs) is actually a really bad deal for most of the participants.