I do feel sorry for you because of the situation you encountered. But I also note that the behavior from the US custom officials would not have been any different. They would behave exactly like the Indian counterparts. It was a colossal mistake and I actually blame US immigration for this. They generally check that you have correct papers before you board the plane. My friend was bit allowed to board the plane when he did not have proper transit visa papers from US. And another one did not have proper papers for his kids when he was visiting India and he was denied boarding the plane too. Before putting all the blame squarely on Indian custom officials, we should consider that they were just following the rules. The frenchman was probably just on transit to India enroute to another destination. Your final destination was India and hence they will check for correct papers.
