It's only stealing when someone posts a meme and claim they created it and came up with the idea. Raydog isn't stealing it because he hasn't claimed that. Sharing it is a more accurate description.
I think people who saw alien in theater have all thought of those clips that way. I saw the meme today but have before that put a clip on my daughters barbie and made same comment. Word of advice 8yr olds might burst into tears if you do that