Air India- ways to avoid/minimize excess baggage costs?
Background: flying India domestic xxx-BOM (with 15kg allowance), staying 2 days, then flying BOM-USA on a separate ticket (with 2x23kg allowance).
The xxx-BOM one-way fare is INR 4000. Excess baggage cost is INR 650/kg, so 15kg = INR 9750.
Can I simply buy a 2nd xxx-BOM ticket (or the equivalent of 'extra seat') to get an additional 15kg allowance for half the cost?
I'm assuming the direct answer is no, but wondering if anyone has insight into other means.