Vending machines Vegas style

I’m skimming Hoare’s Communicating Sequential Processes, a rather technical book on concurrency.

One of the examples discusses a vending machine providing a food sample first, before payment. The vending machine is used as an illustration for Hoare’s theoretical notation.

But think of that vending machine for a moment.

A vending machine which randomly serves free stuff. For example, on average, 10% is served free.

It could work two ways:

  1. Refund the money, "compliments of the house", or
  2. Just walk up and push a random button, free food pops out.

I have a hunch the sales volume would go up. Way, way up.