My 2 cents about a bill for 8 of them

The Consumerist has an amusing tale about a newspaper subscriber who canceled his subscription but can’t seem to get the paper to stop sending him bills for 8 cents. What I want to know is why can’t every software program responsible for such automated billing these days be smart enough to zero out any balance less than, say, the price of postage. Is that hard? It doesn’t seem as though it should be hard.