The 2 PC Rajdhanis are less in number, may be BCT and HWH, these 2 have. They are having it since long to give better treatment to passengers.
Long back they used to be dining cars, so the idea behind having 2 was to make sure passengers do not need to walk long distance to go to dining car.
All new trains have single pantry only. IR does not have so many PCs to give 2 to each train. These trains have it since long and they continue to have it.