The official MAME team has a strict policy: they only include "original" and "official" arcade software. They generally exclude hacks or unofficial modifications to keep their database clean and historically accurate.
: Unlike standard MAME sets, an HBMAME ROM set contains the specific modified .zip files for the hacks. hbmame roms
: Unofficial versions of games that were often found in arcades back in the day. The official MAME team has a strict policy: