THe problem with discrete logic games is that there is nothing to emulate.
Most games use one or more computer processors. Those processors have instructions sets. When you emulate a processor you are basically just emulating the intruction set of that processor (simple explanation, it is more complicated of course).
Discrete logic games have no processor. They just have wires, capacitors, resistors, integrated circuits, and sometimes ROMS. They can be simulated, but never emulated.
To simulate one you would have to basically "write" the entire boardset in software. Not an easy task.
Really, with those discrete games it would probably be a lot easier to dump the graphics data from the roms (if it uses them, most after 1975 do), and then just carefully examine the game and then just make a PC program that does the same thing.
But, there are three major catches with doing it that way.
#1 It won't be exactly the same as the original game. (The Mame Pong driver is not the same as a real Pong). A really dedicated programmer given enough time could probably almost make it perfect though.
#2 Most black & white games are so incredibly ungodly rare (or completely extinct), that they just aren't around for a programmer to examine and then clone.
#3. It couldn't go in Mame because it wasn't emulation. Although if the "program" was written for an emulated processor, rather than for PC, then you could hack in a driver.
I know a bit about this subject because there was a time when there were only 2 known Shark Jaws boardsets in the world. One resided in the Shark Jaws machine at the Videotopia exhibit, and the other one belonged to me. I had it for years, and had no way to play it. I talked to a few game programmers, and one of them told me that the best he could do was to reimplent the game from the (rather detailed) gameplay descriptions in the game manual. But it simply wouldn't be the same.
Imagine trying to write the game Berzerk using only a set of screenshots and a detailed description of the gameplay. Sure it would LOOK like Berzerk. The robots would be there, and Evil Otto would come out, but it would be all wrong. Otto wouldn't move the same, the robots wouldn't have the same behavior. It wouldn't generate the same rooms, etc, etc.