thirty minutes or free

It's one of life's imponderables - does anyone ever get their pizza for free?

Or is it because we are too polite?

When the guy on the moped sits outside your flat, honking his horn impatiently, as though it were you who was late. As you head down the stairs, mentally annoyed because you've stopped the DVD twice convinced that you've heard him honk before. When does that annoyance turn into embarrassment?

Is it because you know that he earns less than the cost of a pizza an hour and if you refuse to pay it might come out of his wages? Is it because he seems so impatient that you think it is your fault? Does it seem really petty to argue over nine minutes?

As you eat your pizza and you glance at the statement "30 minutes or free", does it make the pizza taste not as good because you know you should have it for free? Nine minutes doesn't sound like long. Nine extra minutes to wait for someone to bring food to your door really doesn't sound very long at all. Is it terrible that, as a mathematician, I know that nine minutes is 30% - being wrong by thirty percent is actually being very wrong.

Does anyone ever get their pizza for free? Or do we just not tip as much?