Angry Owner/Account on B&N Store "Demo Devices" are very stubborn

I've been rooting a lot of nooks lately... around 60 of them so far. Some of the nooks I've purchased turned out to be the in-store demo devices. These models just run a loop, advertising the features. My procedure has been:

-using NookManager, reset to the factory image, this wipes out the advertising loop app
-register all the devices to the same email address, for uniformity
-upgrade the devices to 1.2.1 via usb
-use NookManager to root the device
-install my software

However, I've recently come across half a dozen nooks where the factory image IS the advertising loop. These devices are still rootable, however, they are preconfigured in their factory image with their "TEST NOOKUSER" owner and "st284@nk.com" account email address. In addition, the "Erase and Deregister Device" option is grayed out.

Summary of unusualness:
-adb via USB not recognized (ADB works via wifi inside NookManager)
-owner/account not editable
-screen time out greyed out at 2 minutes
-adb install -r pickyourfavorite.apk yields "/system/bin/sh: pm: not found" so this renders installing impossible

For the curious, these units are generally 1.0.0 or 1.1.0 software versions.

What are the ideas on the way forward here? I'm sure a lot of these demo devices will be hitting flea markets.

Anders

Anders