At first I thought that this was a troll thread but then realized maybe there is someone so insensitive that they actually believe this.
I can tell you have no kids because of what you wrote about the gorilla. Little kids go everywhere quickly and you only need to avert you eyes for a moment to look at another kid for something to happen. As far as has been reported, the gorilla kid parents were not doing anything wrong, just distracted for a moment by another child. If they held the kid over the railing or something to get a better view, you would be right but that was just an unfortunate accident. (needing to kill the gorilla is another topic)
As for the gatorattack.....the sign said No Swimming and guess what they weren't swimming. Everywhere else in the country No swimming signs typically mean that there is no lifeguard on duty so don't swim. They don't usually imply No swimming...because you will get eaten if your skin touches water. They are on a body of water that Disney has made to look exactly like a tropical beach with lawnchairs, umbrellas and groomed sand, but you expect everyone to keep well back from the water? They hold movie night there (in fact there were lots people playing in the area where this happened) and the beach is a popular spot for watching fireworks.
People that live in Florida know that all bodies of water harbor gators, but people from Nebraska probably don't.....and there is the presumption that there are no dangerous animals on Disney property ESPECIALLY when the property doesn't warn guests. As far as killing the offending gator, it is the only way to verify which gator did it, they are not endangered and historically once predators get the taste of easy human prey they have a tendency to repeat.
Either way, the parents in both cases were NOT negligent, sometimes bad things happen and it can be devastating.