I could see situations where the offspring of a hybridized animal got sold and eventually bred to a "pure" snake, thus producing hybrids. Some of the hybrids appear very obviously hybridized (to me), but some look similar to "pure" species, especially second or third generation removed. It has happened that the breeder may not even know he was hybridizing; it could be accidental. I hold no animosity to the hybridizers, but I would never do it myself.