One of the main reasons why this is happening so often is, because it works like 95% in all cases and people want to keep their carefully created .inis . And .ini handling is the worst of the worst in MAME, TBH. Each Time if MAME changes something regarding the .inis, its the time where most people think about, if such a update is worth, going through a hell lot of work, in making new .inis or "correcting" old ones. It would be a lot easier, if MAME could update nondestructively like i.e. VLC player does, where you never lose your ini or preferences.