Your point is correct. Many will not travel in AC local.
But I am asking how can you be so sure that not everyone can afford the fare.
Till now whether a person holding good position or holding a lower position both travel in same class.
Also why then FC is so crowded. Lets compare fares
Churchgate...
more... to Bandra
2nd Class:15/-
1st class :70-75/-
AC class:85/-
If a person is paying for FC without any problem then I don't think paying for AC Class is a problem its just Rs10 more.
Also not even God can predict the usefulness and occupancy of the train even without its actual run.
There always be some who cannot pay FC/AC fare so for just them we cannot hamper the development.
For them also existing locals would be some what less crowded so they too can travel with ease.