Do people who use drugs on welfare spend all of that money on drugs? They spend it on food and basic necessities as well that allow them to at least have some form of living standards.
Take that away, and now you have drug addled people with NO money and an addiction that they can no longer sustain outside of crime. Do you think they're gonna say, "well, they pulled my welfare, better get a job so I can sustain my habit". No, they're going to rob and steal and do whatever else they can do, thus an increase in crime, an increase in jail/prison populations and on and on
A lowering of already rock bottom living standards by pulling welfare will inevitably lead to hungry people, which in turn leads to more health problems. More hospital visits in which we, the taxpayer, will foot an enormous bill because you can't turn them away. Welfare is also tied to public housing, right? Pull it and now you have more homeless people, who will also suffer more health problems because they live on the streets. Eating bad food, exposure to elements, etc. All these people will end up at the hospital for one reason or another, adding to our bill
Finally, it sets the precedent that anything tied to fed/state money is fair game for them to invade your personal liberties by demanding a drug test. Some posters before gave some good examples of that, like telling you what to eat or tying drug tests to unemployment, etc. I guess, for me, it's just another way for government to control your life, something I hate.
Now, if you want to argue that we enabled them to become what they are, I'll completely agree with you. We did. And the system is ed. But more government meddling, to me, equates to more expensive in the long run, every time