The problem is that there seems to be people within the company that genuinely want the Riverboat, RoA and TSI gone. The desire to perma dock the Riverboat at least has certainly come up in discussion before, I recall Martin stating there were various pushes over the years to do so.
Keep in mind that filling in RoA and creating new retention ponds elsewhere is probably viewed by some in the company as being easier and less cost prohibitive than expanding outside the railroad berm. The RoA already contains a concrete foundation, so the land it's built on top of is already technically more "developed" compared to the expansion pads which is undeveloped swampy land.