do pet owners sometimes forget that their pets are actually animals and are likely to behave as such?

Yes most people that own animals forget their pets are pets because they are a member of the family no matter how hard it is to say so.

But I make sure my dogs are treated like dogs spoiled dogs but dogs but I do say they are my four legged kids. Same goes with my cats, snake and degus.

I find it highly unlikely someone would forget an animal is an animal unless they're mentally ill. But some people over-do it with their pets and then do get shocked when they act as bad as they've been taught(intentionally or unintentionally, no rules means the animal will act accordingly often and being a "Member of the family" doesn't mean you should treat the animal as something it isn't). Though often I will talk to mine. LOL Occasionally I wonder if they're smarter than we think and wonder just how much they understand(my cat often likes to make me feel stupid)...but to forget they're a pet? No, some people are just extreme with their...love.

If you're referring to incidents where an owner has been injured or killed, then yes. They may not actually think it's not an animal, but they forget that ANY animal has the potential for violence. It may be aggression, anger, frustration, fear, etc.

Things like this tend to not happen much with dogs and cats because these animals have been domesticated for hundreds of years. They have been selectively bred to form close bonds with their "people". When you hear about an owner being killed by their pet, it's usually an exotic or livestock owner. Predatory animals like tigers, lions, snakes, wolves, some monitor lizards, bears, etc may not give their "owner" any problems for years, but with animals like this, all it takes is for you to drop your guard for half a second. You should never, NEVER trust a wild exotic pet to not hurt you.

With livestock, the issue isn't that they're wild. The issue is that they are strong, usually large, quick animals (even big ones, I have an 800 pound farm hog as a pet and while she's never acted aggressive, she could easily outrun me). When they get spooked or angry or scared, they will lash out. I've broken eight ribs from getting slammed into a metal panel fence by a show heifer. I've been bitten on the legs and hands by horses, pigs, and mules. I've been knocked into, off of, and onto fences, gravel roads, rocky pastures, cement floors, steel I beams, and cattle chute panels.

People get used to being able to do things with animals like this and forget basic safety concerns. That's when they get hurt.

I think you are forgetting that humans are also animals.