Hopeful, I certainly get your point about facilities in the poorer sections of the country, and don't think we disagree. Actually, I had kept my comments short and made no references to the poverty of rural Mississippi because I did not want to be accused of being a snooty Yankee making assumptions about life in the south. Damned if you do.... etc. etc.
Since you opened the door, though, I will say this. The point is not that people there or in any number of rural areas in the South are cheap, but that the public facilities in places like rural mississippi are woefully, even criminally inadequate and underfunded because of the generalized poverty. Having lived in the rural South for a time, I have an idea what the high schools involved in this football game probably looked like, as well as the local medical facilities. And as an American, it pains me deeply to think that my fellow citizens in what is the richest country in the world are expected to make do with such substandard sources.
It may very well be that no amount of medical response could have saved that unfortunate young man anyway.
As for your last question, considering that football is a violent game, and people get hurt, I do think it makes perfect sense for there to be at least an EMT with a first aid kit, it not an ambulance at every stadium. If a school district or a town says they cannot afford that, then they need to ask whether they can afford to play football.