They likely made more profit from the outfits at this point then from raw game sales. They are in no hurry for another DoA game when there is X3 + other projects TN has a hand in.
Well if it's any consolation, Xtreme 3's DLC prices make 5's look reasonable (which is something i never thought I would say...ever). $7 for one swimsuit is so ridiculous...
Atleast TN has a good excuse. Sega AM2 on the other hand had some explaining to do.