I'll just throw out the most obvious reason, which any IT professional should know:
Microsoft Product Lifecycle Search
office 2000
http://support.microsoft.com/lifecycle/search/default.aspx?sort=PN&alpha=office+2000&Filter=FilterNOOn that page you will find that the Extended Support Retired date for all of the Office 2000 versions was 7/14/2009. This means that even Critical Security updates will no longer be available for Office 2000 in the future, and no significant product updates have been available since the Mainstream Support Retired date of 6/30/2004.
Any IT Support person or contracted organization who provided Microsoft products and didn't know how to determine this would be immediately suspect in my book. This is basic support 101 for those purporting to provide and support Microsoft products.
Rob