Plea bargaining should be abolished because it really amounts to a conviction without a trial. And if you think all drug users are guilty of "really nasty stuff," then that should be the basis for conviction - not merely smoking a joint or doing a line.
You know very well that in a service economy that if you are convicted of a felony involving theft or conversion your employment opportunities are destroyed. On the other hand, copping a plea to dope should keep you near the cash register in most cases, although maybe not stocking shelves.