To understand the phenomenon of Indians, blacks, etc. making fun of White people because of their eating habits, we must first understand the underlying chemistry.
First, there is no such thing as the "spicy" taste. Mammals' taste buds can distinguish sweetness, saltiness, etc., but the burning sensation of spiciness is literally just pain. The hotness you feel while eating certain foods is caused by chemical compounds burning through the delicate flesh of your mouth.
Capsaicin – the most common chemical compound responsible for perceiving spiciness – is corrosive. It does to the microorganisms the same thing it does to your tissue: it burns through their membranes, killing most of the bacteria.
Another important thing that we have to remember is that if we add enough capsaicin to our food, the resulting sensation of hotness is going to mask a lot of the taste. It takes away from the complexity of the flavor, but then you cannot tell if the food is fresh or rotten. That is quite handy for the street vendors, I suppose.
So imagine being proud of having your sense of taste impaired. Imagine bragging about eating the substance causing you literal pain... just because your people do not understand the concept of basic hygiene. Hardly something to boast about, is it?
That is to say, cultures who didn't preserve their food, let it partially rot, and then ate it anyways started getting chronically sick, and people who ate tons of capsaicin didn't suffer those same health problems. Healthier is sexier, so over time, parasite-ridden cultures selected for natural and cultural(/dietary) resistance to gut parasites.
This is why you can't trust spics or jeets with your food. You think they'd worry about your food quality more than their own? Never.