It was unfortunately a very big oversight on the part of the parents to not secure visas for their kids. Question is what papers were being faxed from Boston?
Does India grant Visas on arrival?
If not, the kids would be in a spot anyway as transit Visas (even if they had been granted) are not valid for the length of time that they would be staying in the country.
If yes, then the immigrations officers' actions need to be questioned
In any case this is a lesson to all of us to take Indian Immigration seriously. We go to all lenghts to make sure there are no problems on arrival in the US. Why should our own country's laws be taken lightly then?