Oh dear, confusion all over the place....
1- It has nothing to do with 'all enigma boxes', but with the image.
2- All not-PLi based images use etc/tuxbox as the one & only only location for the file.
All PLi-based images (such as ViX) have a system file in etc/tuxbox. A system file should never be overwritten, as then your file will be overwritten again during an image update.
The user file for PLi-based images should go to etc/enigma2: it takes precedence over the system file