For me, two reasons; one is that I would have an easy-to-use announce button to announce the item up for bid, and I also plan to have a field where the raid looter could enter the DKP spent, putting all the information in a single easily filterable line.
I haven't played with EQDKP before; when I tried searching for it a while back all I found were pay services or packages that assumed you were either a programmer or web admin, neither of which am I. My only knowledge of XML comes from looking through existing interfaces here, breaking them and fixing them to do extra stuff I want to do.
I may look into eqdkp again, using your link, but for the time being this is a fun exercise, and I'm learning
