Would you want to know if the person you just hired as your company controller just finished a 12-month sentence for fraud and embezzlement? Would you want to know if the applicants for that new playground supervisor position have ever been convicted of child abuse? Sometimes it makes sense to require disclosure of crimes.
I could do away with reporting drug-related offenses. On the other hand, you'd be amazed how much fraud and theft has drug use behind it. Drugs are expensive and users get desperate.