No sensible person will lend money for gambling and the same logic he applied in this case because if he allowed pay later option then people will just use it and if they lost then they will just close their account and the compnay will just deal with the defaults so he is making the right move by saying no. And there is nothing to debate about this even some countries and their banks have rules like they are not allowing their cards for gambling deposits and this is no different from it.