Not sure how you can compare kids to animals or pets. Doing so in the context that you are, then do those parents teach the "kids" to do their business in a litter box or eat and drink from a bowl on the floor and teach them tricks like shake a paw and fetch?
Animals have animal instincts and always will. Some are raised indoors and have no problem staying there, others crawl the walls to get outside. I had a cat for 18 years (RIP Felix) and it was an indoor/outdoor cat and sure he brought home a few "presents," but rarely wandered from the back or front yard. I set up a sandbox in the back for him to do his business and it worked pretty good. Some can be trained to stay on a leash in the yard, but most would hang themselves unintentionally because that's just not the way a cat is meant to be. People say it is cruel to let them go outdoors, I think it is cruel to keep them in 24/7.
This person who is feeding feral cats probably has problems of his or her own and it should be brought to the attention of Animal Control. Sounds like there are too many.
Also, I am a responsible dog owner and always stoop and scoop, but every single day I walk my dog, I see dog feces all over the parks, sidewalks, walkways, and it ticks me off. I've stepped in it so many times while walking and looking up taking photographs that that gets under my skin more than the occasional pet cat in the neighborhood. At least they bury theirs.
I can almost guarantee humans have done more damage to wildlife and property than any pet cat ever has or will.
Also just my opinion