[This is going to be a little hard to explain to someone from a world like Zelda's, and Shun considers how best to do so in a way that highlights the main issue with that idea.]

You're missing the fact that cutting things off at the source is a lot more complicated in a world like this one. Those toys would be made by a company in a factory hell knows where, or maybe even more than one. Even if we find the source, there's no guarantee we'd be able to follow the supply chain and get rid of all the sources in time to stop this.

[It would take them at least days, which isn't particularly promising when they could probably wipe out these things within one or two.]