Two of my friends worked in a small, two-screen movie theater in the 90s. Since the theater was so small, the ticket booth ripped your ticket for your and you walked right into the screening room. My friends started saving the ripped tickets and handing them out to the next person in line that paid with cash. They made so much money they had to buy stuff and make up excuses about getting it from friends to keep their parents from asking why their checking accounts were so big. So, rudimentary theft plus money laundering, committed by high school students.
They pulled that off for all four years of high school and never got caught. Both of them were my roommates in college and they threw ridiculous parties.