"That's what every employer wants, some tweaker running his equipment."

"Some tweaker" is a prejudiced statement. You can't paint all users with the same brush. Many employees use meth, like coffee, and neither their behavior nor reliability is negatively impacted. Many times you won't even know someone is using (unless you knew about their 2nd full time job.)

Who are you to judge if no harm has been done?

If an employee is doing their job well, isn't that enough? If they aren't doing it well, does it matter why not?

"Perhaps there are actually people in Santa Cruz who think that quite a few drug addicts are forced to commit crimes in order to support their habit, and therefore they wish to take action?"

Then let them take action for THOSE crimes, rather than treating as criminals an entire class of people who have done no wrong and only "might" commit "some" crime according to your prejudice. What is this, Minority Report?

Why don't you make freedom a crime. After all, freedom of choice leads to crime.

Why not make poverty a crime? If you think drug use "forces" people to steal, well poverty is no different. Let's just arrest all of the poor.