Imo, from what I've seen and felt is they want to have a set number of Haven staff and that was reduced under FDR over the years. I'm sure one poster will want proof or charts. Sorry, I don't have any but I certainly have actually sailed Haven enough and gotten feedback from staff of that happening corroborated by years of reports of varying levels of service even from the same staff but different room.
Also, when FAS first came out, Haven got it for free. They obviously took the opportunity to capitalize on charging. If they are able to continually raise prices, charge higher dsc, etc., good for them, not for me.