tubemonkey, you asked about selling the digital copy that's bundled with a Blu-Ray disc ... Yes, I think from the standpoint of the producer, it is considered illegal to sell or give away the digital copy, because you actually just received a license for it along with your bought Blu-Ray. Most digital content, including paid for e-books on Amazon, B&N, etc., are not "owned" but licensed. Content producers do not treat digital content the same as physical, which often falls under the first sale doctrine (that allows libraries to do what they do) that says once you own it, you can lend or sell it. Libraries can make archival copies of media items, but they can't make additional copies to lend out to people (just like you can't legally burn a CD you bought to sell to someone, but you can sell that original CD just fine).
OverDrive tells libraries that they "purchase" and "own" the books they select for their OverDrive library (and each copy = one person lending at a time), but they only have access or can lay claim to that e-book as long as they are subscribing to OverDrive. If the company fails, or the library decides it can't continue the ridiculous increases of maintenance fees, then they lose all that the invested money and that collection of ebooks.
Without seeing the Terms of Use on your digital copy, I can't say for sure you don't own it, but I've yet to see full, true ownership rights given through digital movie copies. Of course, if you gave the digital copy to someone, the original, not a copy of the copy, I don't know if there's any way for that to be tracked and proven as a violation? Personally, I don't think it's wrong to give that license key away as a whole entity and not a copy of it, but the law hasn't been interpreted firmly on the end user's side for a while now.
