Only one thought comes to mind. Wild plants don't always have the soil nutrition and watering that domesticated plants do. I've noticed that while I don't get as many or as big a Black raspberries from the wild areas of my yard as the ones that I transplanted into a bed, the flavor is much more intense. Like with herbs-most of the thyme's and oregano's that are the most fragrant/flavorful are the ones that are growing wild in soil that is not as nutritious as the soil in my beds. They are also better tasting where they are more stressed.
Hot peppers will also be much hotter if the plants are stressed and left dryer. If I want milder peppers I often watered every day for a week before picking. the moisture kinda dilutes the hot.
Does that make sense?