It's probably a marketing trick, it's worth a mil yes, but it's distributed over across every participant in the airdrop, which can easily number to over a million in most cases, so most people wouldn't be getting that much. You'd be lucky if you got something over $50 really. As for it being a scam, if it's free then yea most likely. If it's not, and you gotta do something, I'd believe it isn't. In general I try to avoid getting stuff downloaded when it comes to airdrops, if it were to say, tweet something, do a survey or whatnot sure, scam or not you'd honestly be safe imo, but if it includes putting something inside my computer from the internet, pass.