Sounds like a problem mostly for premium travellers. I think most economy travellers without lounge access would happily accept and indulge in any complimentary meal at whatever time they are offered.
One could argue that you are testing the limits of those rules by flying and crediting to separate FFP to that which you are using to gain lounge access.
One downside of booking the night before which has not already been mentioned is that it is not budget friendly although I sense that unlike for me, this is not usually an issue for most AFFers.