I've seen kittens born in the wild from a feral and domestic parents that never were tame enough to let anyone touch them even after they reached adulthood. Oh sure they will take food just like a bird/coon or park deer/etc......but they make poor cuddly pets. Were not talking about a poor alley cat having kittens.
IMO some of the folks replying don't understand what a feral animal is. Hell we have a very serious feral hog problem in my area. Most folks know where feral hogs came from and how/why they stay feral. It takes several cycles of breeding with domestic hogs to get rid of the wildness/aggression.
Cats are no different.