No questions about it. There is some additional cost to convert rupees to conventional money, e.g. $, gold, Euros, Yen...   So, this is just another discount in addition to transport, insurance, reduced price, bribing...) Russia is paying to bypass western sanctions. 

 

My point was that  prior to this war India somehow had paid for conversion, now it's Russian "problem".  An overall  amount is estimated to be ~$1B/month.  It doesn't look that losses are very large, as there should be several ways to spread it around, you just go here and there, paying along the way.   So instead of X discount they are getting X+Y and many people on both sides are getting rich along the way.