Devices like the Raspberry Pi (using RetroPie ) or older Android phones use 0.72 because it requires significantly less processing power than modern MAME versions.
The popular MAME 2003 core in RetroArch is based on version 0.72. MAME 0.72 ROM Collection -ROMs- by Lovok
In the world of arcade emulation, software and ROM files are intrinsically linked. Because MAME aims for perfect documentation of arcade hardware, a game’s code may be redumped or restructured in later versions to improve accuracy. This means that modern ROMs often won't work on older emulator versions and vice versa. Devices like the Raspberry Pi (using RetroPie )