In Jennifers post on the forum that you linked to, post 41 says:
No essay scanned by the Viper software has or would ever appear in an essay bank for resale - again our contract with the user permits us to retain a copy of their essay so that future users can scan against it (this is kept 100% confidential so no other student, scanner or university could view this essay, ever), and the user gets no payment for us retaining that copy of the essay - but then, neither do we charge from the software. Viper has cost us thousands on thousands of pounds to develop so the fact that we retain a copy of the essay for future scans to check against, is a small price to pay for using the software. It actually improves the accuracy of the results so benefits the student in the long run.
However the terms on scanmyessay.com says:
By using the Viper software you further acknowledge and agree that Academic Answers Limited will retain any document processed by the program and may use such documents for the purpose of marketing Viper, or any associated website of the Company, and you agree that any right you may have to remuneration for the use of documents to which you hold the copyright is waived. Academic Answers Limited agree not to use documents processed by the program without your consent, and in any event, not within six months of the document being processed.
I'm confused, are they using the essays on their sites or not?