I'm speculating, but it might be a number designed to discourage purchase rather than reflect actual value. IE, we don't want personal users to buy these so we

I'm speculating, but it might be a number designed to discourage purchase rather than reflect actual value. IE, we don't want personal users to buy these so we will price it higher than their data is worth but low enough that we won't completely alienate potential corporate clients. They don't want regular users getting the idea that they can opt out by paying extra because it messes with their whole business model. FB is just dark patterns all the way down.