Google gives Ozdirect zombie immortality at comparison shopping

How long do dead onlineshops live on in Google?
Thats become an interesting question because of the story I published at eCommerce Report last week.
The story reported that online merchant -www.ozdirect.com.au - had finally been found guilty of taking peoples money and not supplying the goods.
Ozdirect's websites closed down some months ago however, and authorities report that the whereabouts of Paul Albright, - the founder and a director of Ozdirect Online Brands Pty Ltd - is unknown.
Even so, as I wrote in my story, a search for Ozdirect at Google Australia last week revealed that Ozdirect listings were still up at leading comparison shopping sites including the local version of eBay's shopping.com and its Australian partner - ninemsn.
As I write this, they've been taken down.
In fact, barely hours after the story was published, both Adam Canter from Shopping.com, and Mikaela Lancaster from ninemsn were in contact.
Adam attacked the factual accuracy of the story.

"There are no Ozdirect listings at shopping.com

said Canter.
Mikaela said that she had removed any references to Ozdirect after reading an earlier story about Ozdirect in eCommerce Report.
I replied that Google was still clearly finding listings, even if clicking through ultimately led to a parked domain for one of Albright's other domains - www.ausbuys.com
I declined the request to alter my story or retract the claim, and invited both to comment.
Only Mikaela took up the invitation.
It is of course, problematic, that pages from dead sites should continue to show up in Google.
Perhaps its inevitable because of the way in which comparison sites construct their listings and pages.
My understanding of their technology is limited but I believe that Shopping.com, GetPrice, ShopFerret and the like all use the same XML approach, incorporating an RSS feed.
That should mean an end to any listings from a failed merchant as soon as the merchants' site disappears.
I'd be any grateful for any suggestions as to why that doesn't happen and, why, in effect the comparison sites carry zombie listings for a while afterwards.