Tldr: watching a video of taking a product out of its packaging gives people the vicarious feeling of newness and ownership without actually buying the product. This is popular it seems, and largest effect is in toddlers.

It's just another trigger the modern world has uncovered in our ape brains. The thrill of unwrapping a banana or mango writ large. It probably won't hurt your kids but if they are watching videos unsupervised and you "come across" them watching that's probably a bigger flag to you.