I don’t see how it’s any more realistic than “a worker who needs money to (make his next car payment/buy his fiancee an engagement ring/take a trip to Maui) figures he could sell company secrets.” Sure, it’s possible, but the actual problem is unrelated to drugs.
I specifically mentioned underage drinking and smoking because they are illegal. The specific laws may vary, but generally if a minor has cigarettes or beer in his hand, at least one crime was committed to put it there.
The minor depends on someone to supply him with nicotine or alcohol–a crooked clerk, an older friend, or a stranger walking into a convenience store–and if he’s addicted, he has a habit to support (which has nothing to do with legality).
Well, I don’t want to worry about an employee not being able to work for several months because she has to support a child, or stealing from work to support the child, and that’s a helluva lot more concrete. Pregnant employees will take maternity leave in nearly all instances, and they’re going to need a lot of money to raise that kid. But going from “Jones smoked pot sometime in the past 45 days” to “Jones is going to raid the cash register” is a HUGE leap.
If an employee shows up late or hung over, fire him. What’s the problem?