Sometimes you get lucky dumpster-diving, too... ;-) I know *I* am not above taking a rib-bruise for the right piece of gear! ;-)
But since we are speculating anyway, let's guess that "facemd" is a specialist in maxillofacial surgery. He does charity work down in third-world countries where children's cleft palates often go uncorrected until volunteer docs can attend to them. As he does his charity, he finds another charitable organization ready to dump a stock of educational tools (the TI's) because they can't appropriately use them in village school settings. He offers to take them off their hands, knowing that back in the states they may fetch enough money to pay for badly-needed medical supplies and water-treatment or perhaps paying for the airlift of a particularly difficult case to an urban hospital where a prolonged rebuild can make functional, a human baby whom others may have seen as a hopeless punishment on their family. Thus even a TI can have merit...
Or maybe "facemd" works in the San Diego docks and the 4000 TIs he displaced from the shipment made room for whatever needed smuggling or disposing of.... Yes, maybe the "Face Doctor" got his name not from a diploma, but by practising his handiwork on stool-pigeons and those who got too close to the Asian pipeline where he stands guard at one end... but part of his payoff is in the import goods diverted to make way for the "real" goods. He only sells them after the "heat" has worn off the merchandise...
Either way, if he's looking for someone with a hankering for 4000 of the same calc to pop up with 20K, we can surmise he is either in no particular hurry to liquidate this stock "fire-sale"-style, or he needs a lot of cash with minimal fuss; he doesn't want to operate a business of selling calcs. But some veteran eBay Power Seller will undoubtedly come along and then sell them one at a time for the next three years at $10 each to unsuspecting calc newbies.
Yes, there are a million stories in this naked ebay.... :-D
