Privacy

I agree the OP's use case isn't life-or-death and therefore doesn't need the highest quality faraday bag, but they asked for ones that work, so I felt it pertinent to point out that "any chip bag" was not, in my view, a particularly good recommendation. It's cheap and accessible, but isn't going to work as well (or at all) compared to a bag that was designed to block signals.

In this instance, you get what you pay for. OP is free to try the chip bag method, but they ought not be surprised if it's an insufficient solution.