A dangerous precedent to be set though. It's good to know that every war we think we will win we can talk trash after 48h, and then rationalize that to take/destroy all their resources after EoWCF. If every kingdom that left war from a position of strength did this to their opposing kingdom, that would definitely not be healthy for the game.
But in the end, as Sampuan has said, it isn't getting waved that we care about, it is that the whole chain of events makes no sense. If they were just doing it for resources they could have done that from a position of strength prior to the war. The problem is they havent really come to the table with any realistic offer. Their idea is just to wave and wave a kingdom not fighting back. Yes this is different than last age when we hit kingdoms from strength as we only did 1 wave (usually just a partial wave) against kingdoms, and were very open to CF's, the only time we did more than 1 wave on a kingdom was when they were hitting back and/or not coming to the table for a CF.