I think I would reword your question to say "why does it seem like some people or organizations think animals and humans should be treated in the same way?
Some may put more value on animals, and object to drug testing, rodeos, and other activities.
These people probably think that people should be able to take care of themselves or that other people will look out for them. They also believe that many people do not care about animals and abuse them in many ways.
Well, we know all people do not get the help they need from others. I also belive that animals were put on earth as a lower species to provide, a source of food, a source of labor and a source of companionship. I have no problem ordering a steak in a restaurant (except payng for it) knowing that a cow had to be slaughtered so I could have the meal. I have no problems if animals are used for test subjects, as long as the tests are done as humanely as possible.
I have no problem withe elephants being use to raise the circus tent, horses use for transportation, etc.
I have three beagles--a source of companionship I would never give up.
Some people, just have trouble seeing the whole picture.
Other people--those who abuse animals, like dog fights, cock fights and other outlandish things, or people who kick or hurt animals just because they want too--perhaps make it necessary that we have people who do want to look after the animals that supply so much to our quality of life.