RichardL, correct, some OEM software can be illegal, and anything that ships without hardware or with instructions that it cannot be registered should be considered suspect.
But most OEM software is legit. I have bought plenty of OEM versions of operating systems, some stamped with Dell or Gateway logo, through liquidation houses. They invariably show up at my door with some piece of hardware in the box...an old dongle, and old vga card, a corded mouse...hardware that is worthless, but included to allow the sale to be legit.
TJR