Just be wary of the licensing issues.

A lot of OEM software is licensed only for distribution with a new PC or other peripherals/hardware. Retailers who supply in breach of this are being a bit naughty. They are effectively gaining a bit of an unfair advantage over their law-abiding competitors. I wont make a judgement about those purchasers that make such purchasing decisions - it's up to them at the end of the day.

It follows that users may also be using the said software in breach of the developer's licensing conditions, and whilst the developer will very likely never find out, this could impact upon the user's entitlement to free support or upgrades.