Release the hounds!

Okay, I'm selling a ton of stuff on eBay (username "piercepresley"; inventive, I know), lots of software and various tech items, figuring I'll get a better price that way than putting them on a table at our next garage sale (tentatively scheduled for the turn of the next millenium—we're still recovering from the last one). One of the items was a copy of Microsoft Office 2000 Professional, which someone representing themselves as representing a church bought (of course, online, no one knows you're a dog) bought using the "buy it now" thing where you pay a set price on an item that as yet has no bids.
Now, I know I like promptness when I buy something, so I did the golden-rule thing and printed out a shipping label and packing slip (sometime I'll wax eloquent in praise of the eBay-PayPal marriage made in heaven), put everything in a bubble envelope and took it to the post office this afternoon to get it right off ASAP.
After dinner, I took a peek at eBay and noticed that the items sold list was down one. In my e-mail was a letter from eBay saying they had removed the listing because, basically, Microsoft had asked them to because the latter thought I was selling a version of the software that is discounted and to be sold as part of a premade computer (or with significant hardware, like a processor or hard drive). It's called an OEM (Original Equipment Manufacturer) version.
Now, someone had asked me whether the software was new or used, OEM or retail. I answered honestly, and I think I said that while I believed it to be a retail version, it was possible that I bought it as OEM with the approprate hardware. (EBay has pulled the listing altogether, so I can't check what exactly I said.) But I also made it clear that I was not selling it as new, and that I had used it myself.
While I think the "licensing" of software is a travesty almost on a par with "business method" patents, I can understand that Microsoft doesn't want people buying up discounted software under certain rules then reselling it without continuing to follow those rules; that's fraud, any way you slice it, and I hate fraud. But we're not talking about Lucky's Pawn and Software, we're talking about Pierce Presley, individual, selling a CD-ROM and manual from a piece of software that's no longer on any of my computers and that I have even purchased an upgrade to (and I was planning on using some of the proceeds from the eBay sales to upgrade yet again).
I've shot a letter to eBay and Microsoft explaining my position. I don't know that it'll do anything for me, and I expect that as the product has already been paid for and shipped that the transaction will stand. But I got to wonder, how much of the price of a Microsoft product goes into preventing that man, Pierce Presley, from selling Office 2000 Pro?
Just to cover my ass, all trademarks used in this post are used in an editorial, good-faith sense and are not intended to infringe upon the rights of the holders. Your mileage may vary. Caution! Coffee may be hot. This is not a lifesaving device.