The prologue (first ten minutes) a recently recycled episode of This American Life podcast addresses how consumers can be taken advantage of by creditors if they neglect to show up to small claims court.
According to the podcast, creditors often times rely on consumers not showing up to court in order for the judgement to be decided in their favor. If consumers show up and ask for the evidence of how the amount was determined, it usually cannot be produced and the case is dropped.
There are some consumers who try to take advantage of getting out of their debts due to a lack of evidence, but this has backfired.
The moral of this story is simply to know what the basis of any debt is before blindly paying it or neglecting to appear before a small claims court to ask for the evidence that the amount is based in fact and not some fabricated work of art by the creditor.