Why do they all say "rare" 3 door

[capev86]

1935-1966 2 door: 31 years
1967-1972 3 door: 5 years
1973-2010 4 door: 37 years

you could say the 3 door trucks made over a short span of 5 years makes them kinda rare. combine that with the fact that most have rusted away or been parted out years ago. but really, it is just a selling gag to get the attention of those not in the know.....