I used to get not full on sick, but pretty sick after eating raw or partially raw meat. You may think it's crazy, but I just continued doing it and eventually stopped getting diarrhea and cramps.
David Blaine (I think) talked about a similar effect from when he practiced swallowing live frogs. He got sick initially (not gag reflex but something akin to food poisoning) but quickly built up a tolerance.
Maybe these guys did get sick in some way that is beyond a reasonable risk tolerance. I don't know. I just think Americans in particular are weird about their food and simultaneously germophobic so they end up eating a certain kind of diet. Getting sick when eating food that isn't totally cooked may not necessarily mean danger but that the body isn't acclimated to the particular food.