These people would make these videos to get 500K. Maybe the most popular respondent will get 2 million NEM? As an incentive to make a video and to get views.
Giving away millions or maybe 1 billion nem would mean Nem would be pretty worthless, just like most other recently launched coins. These people will dump them fast. The recent history has shown that more free "giveaways" the more worthless the coin. All top coins (including bitcoin) are actually controlled by very few people
I am already feeling bad for people who bought nem by spending real money on nxt asset exchange, as we are about to be flooded by giveaways that will lower down the prices significantly.
I would rather see unclaimed coins destroyed.