In Law there is no logic for anything generally ., still ..........................

Practically as per norms & terms of Indian Govt. With Nepal/Bhutan Indian currency is workable in those countries therefore there is no need for foreign currency. 

In Rule 3 Schedule I there is generaaly prohibition on use of foreign currency except "lottery income" it is probition on source of income.

Hmmm... I dont think so coz there is always a logic behind a law being made. Just couldnt find it on google..

Anyways thankx for your reply.