Daughter just applied at a high-end grocery chain. Had to answer 7 pages of questions on a computer "test". It was all about drugs and stealing...would you, do you, when did you, will you, how long did you, how much...it went on and on. Then at the end you signed the paper agreeing to the drug test. She just laughed as she answered the questions and signed the paper. She had nothing to worry about. This is just for a grocery, no heavy machinery or life threatening positions. (Fork-lifts aside, but she just wants to be a checker!)
I believe an employer has the right to expect drug-free employees, just like employees expect to be paid for the work they do. You can be the most honest, drug-free person in the world, but because of the people who are NOT, they have had to change the rules and expectations for hire. That's okay. To me it's no different than going through the metal detectors and letting them search your bags if need be when getting on an airplane these days. YOU know you don't have weapons, but if you want on that plane, you go with the flow or find another means of transportation. Simple concept.