Pet peeve: making up numbers

A few days ago while channel-surfing I accidentally landed on C-SPAN and watched one of the famous "Town Hall Meetings" about healthcare reform; that particular one was in Towson, Maryland. (I don't remember the name of the participating Senator.) At any rate, here's what stuck to my memory: a member of the audience asked a question about the costs of public insurance fraud; he said that the current costs of Medicare/Medicaid fraud are estimated at $20 billion, and so what are we going to do when, after enacting the public option, those costs go up to $1 trillion?

Seriously: why is it that some people think that if their statement contains a number it somehow becomes more credible, even if that number is quite obviously entirely made up? Who in their right mind would believe that after enacting the public option, the costs of insurance fraud would somehow jump by three orders of magnitude? And since we're making this sh*t up as we go along anyway, why stop at trillion? Why not quintillion, or googolplex, or $24.56?

The answer to the last question is probably that, if you're engaging in pretentious number-dropping, you'll want your number to sound "scary but not too scary" to someone stupid enough to think it has any justification to begin with.