Hey fucktards, I believe I can help solve this great mystery of yours:
It's actually a VERY ingenious marketing gimmick.
No one is going to buy 6 of those turds at a time. However, I guarantee that every message board on the planet is going to have some fuckstick post this "OMFG 6 WRX LOLOLOL STUP1D!!!111!!1! KEKEKEKEK!!11!11!11"
Now, stay with me here.
Someone in those 508469584968790468470986798694076 message board members will be looking for a 2005 STI and, you guessed it, will see that auction! It costs the dealer, what, about $50 in ebay fees since it won't sell but it will advertise like no newspaper or online ad service could even have a wet dream about.
Whoever had that idea at the dealer deserves a raise. Hell, they should own the dealership. They have effectively used the ignorance and gullibility of todays youth for their own gain. I think it's awesome.
You can thank me for solving this great mystery for you by PayPal'ing me $10. Thanks.