First point closes the circuit to charge coil. The current is near zero for lower RPM, no "make" spark. It gets little wear. The other point carries the current after first point, but opening "break", it creates the spark, that is when erosion occurs. The condenser helps avoid arcing.
Might be the condenser. Have you changed it? Might also be return spring lost tension, needs lubrication, both could result in chatter or bounce, making more sparks and erosion. Any of the problems also reduce spark energy to plugs.
Also better quality points are vented, the peak, fits in the vent hole. Not sure what dual points used.
When I used points in the late 60's 10k miles, was past the optimal point