I think you're referring to something different. The "request key" is what you request from Freenet, but it transformed into a "store key" (not official Freene

I think you're referring to something different. The "request key" is what you request from Freenet, but it transformed into a "store key" (not official Freenet terminology) before the request is sent out over the network. If you have the encrypted content you only see the "store key", but the "request key" is required if you actually want to decrypt it. This means that, to see what content you're actually storing, you'd need to go to a lot of trouble (basically a dictionary attack on the store key). Not impossible, but enough for plausible deniability.