They also put a quarter-million copies through the crazy expensive (at the time) laser jet printer that I'd just bought a few months prior, paying over $3,000. They kept it for 4 years, 364 days, the longest they could legally hold on to it without charging me with anything.

Use the government's math - don't just charge them the cost of the jellybeans, charge them for the jar, the desk, and add in the hours you spent buying them multiplied by your wage.