There’s a long history of people misunderstanding the purpose of quotation marks and using them for emphasis. It’s not quite to the point where the misunderstanding has taken over, and at this point it is unlikely given the fact that asterisks seem to have overtaken that role, but I remember memes about this from twenty years ago or so.

It’s even more pronounced in countries where English is not a primary language, which is likely where most silica gel packets are packed.