Well Microsoft are a business, and they spend a lot of money creating their Ofice products, and then supporting them and providing fixes for them, so why should they give it away for free.
Do you go to work every day but tell your boss not to bother to pay you?
Microsoft have produced a version of Office 2007 called Home and Student edition that includes Word and can be bought for about �60 (it can also legally be put on 3 PCs).
http://www.amazon.co.uk/Microsoft-Office-2007- Student-Licence/dp/B000HCZ8EO/ref=sr_1_1?ie=UT F8&s=software&qid=1234010275&sr=8-1
If you still have the old version of Microsoft Office you had on your old PC there is no reason why you cant install it on your new PC (assuming it is no longer running on your old PC).
Finally, if enough people installed and used OpenOffice then maybe IT would become the standard and the world could stop worrying about having to support Microsoft's standards.