I have seen on craigslist why people put fake ads on..
On Craigslist people put many fake ads on to make all the other people that look to try and find a cheap deal give up.
So people get fed up and never look anymore. This then gives all the genuine sales to the person that puts the fake auction up.
It's a really awful thing to do. But greedy people do it in the hope they get a Quantum or Major Havoc for $200.
I guess the someone is doing the same thing on marketplaats - to try and piss you guys off so you won't look anymore and they get the real games for cheap with less people contacting the seller.
It's probably someone on this forum too.
