For me gambling does not increase crime but rather increase addiction to some people who does not know how to handle it properly. When it comes to crime, for me the number 1 aspect is drugs next is poverty. I don't consider gambling unless it was also associated with drugs.
And where do you think a gambler's life lead? It's definitely leading to poverty since money is involved. Druggies only have to buy a dollar worth of drug and they are good to go. Gamblers, on the other hand, have you really seen a gambler lose one dollar in a casino and then move on? Drugs are far more cheaper than gambling. Once a gambler has lost everything due to gambling, and I'm talking about to the point where he had to sell his properties and belongings, he's going to be homeless and start doing bad things just to survive. At first it will be just as simple as lying, then manipulation, then comes the selling of the small things such as jewelries, and so on. You get the picture.Just so you know, it's not the drugs that makes people want to do crime. It's the addiction itself. They want to feed the addiction and so they commit crime. I mean, it would be so hard to steal when you're stoned. You can't even get off the couch.
But if a gambler was playing he wouldn't commit a crime in the process either. I agree with you that it's the addiction not drugs or gambling by itself what makes people to commit crimes, but those kinds of addictions are very different. You can be distracted by something interesting and forget about gambling even being addicted to it, while this can't happen with drug addiction because you feel physical pain during withdrawals which can't be ignored.
Gambling has been historically intertwined with criminal activity but the connection has becoming weaker with the implementation of online gambling.