Also, what if the emails don't bounce? That then means Google holds them hostage, and the only way he'll ever get them is to pay for the upgrade. The senders wi

Also, what if the emails don't bounce? That then means Google holds them hostage, and the only way he'll ever get them is to pay for the upgrade. The senders will never now they didn't get through. I don't think that approach would be very welcomed by the majority of users.