Whats with all this humans AND animals stuff. Humans ARE animals!
With this in mind it's absurd to suggest, as any carcuss eating 
mentally stunted moron has that theres no comparison between 
killing an animal and the human animal. You'd have to be 
desensitised to do either. Take a slaughter-house for example. To
be able to surround yourself with death and mutilation and not 
crack up, would be the same as being in a war and not doing likewise.
You'd have to be able to detach yourself from the reality that your 
slaughtering sentient beings or you just couldn't do it. Theres no
great surprise that the Jeffrey dahmers and Fred Wests of this world
worked in this environment. As for plants, are meat-eaters being
witty when they say this?? or are they, most likely just that full 
of denial that they cant see the reality because they've been blinkered
and brain-washed by there establishment? Plants have NO central 
nervous system so quite simply you cant consider yourself scientific
and then suggest that their capable of thought or feeling, your brain
tells you that your hurting! Killing an animal is killing an animal
even if it's the human animal.