But now after reading:
"And finally, to satisfy the law in some countries – no purchase is necessary. You will be entered into the competition by simply registering your name in our store. But, if you do this, while within the letter of the law you are of course defeating the purpose of the whole exercise. You must decide if that's really what you want to do."
I'm more than a little annoyed by this self-serving you must decide. It's either the law or not the law, rather than what we choose to do. I refuse to have a guilty conscience, ignoring the fact that I've bought quite a few of the LL videos in the past, and will enter anyway.
This is really rather silly.
Michael is running what is in essence a small lottery. He's doing it partly for fun and partly to increase sales from this excellent site. The law insists that such lotteries must not make any purchase a prerequisite to entry, so he makes it perfectly clear that you can enter without buying anything.
But this isn't a public lottery: it's one that's made available to a small community (using the word in a pretty loose sense) of like-minded (usually) people. We come here to use the site because we like it and consider that Michael performs a service to us in general by making it available.
There's nothing "self-serving" about his last couple of sentences: he's just making his motivation crystal clear to anyone who hasn't already reached the obvious conclusion.
Of course you can choose to enter the competition without buying anything, just as you can use shareware without paying for it. As long as only a few stingy individuals act like that, no harm is done. But if the habit becomes widespread, we all lose. It's a modern version of the prisoner's dilemma.
If you act as you suggest you're going to, you'll have behaved dishonourably, albeit legally, and should feel thoroughly ashamed of yourself - particularly if you win.
Jeremy