I have to go through the threads again to get why others have done it that way. But, the gist of it was that silica could absorb/contaminate the raws if vacuumed in the same bag. What moisture in the powder could still be absorbed.
Practically speaking, when I recieved my raws over summer, the heat affected the raw in the water-tight wrapping. The bag felt like a ball surrounded by jelly/liquid. I could only assume that it started melting in the heat. After placing it indoors overnight, the entire bag felt hard as a rock, taking the shape I left it on the table. Again, I could only assume it part of it melted and turned liquid, but I could not see, as I did not open the sealed raw bag.
So I imagine if the raw can melt and turn liquid, it can possible get sucked up/contaminated by the silica.
I'm open if anyone has a better take.