What you said may possibly be true in that humans many not be able survive without destroying other species.
Also, the Buddha did teach 'karma' is 'intention' therefore the Buddha did not generally directly admonish or criticize people for killing animals for food for their personal or family consumption.
However, the Buddha did say carrying on a business from the slaughter of animals is wrong livelihood probably because this involves concentrated killing en-mass.
For example, in the chicken factory, the workers must spend 8 hours per day killing chickens or watching chickens being killed, dismembered, gutted & processed.
This has been shown by psychological studies to have severe adverse psychological impacts upon the workers, such as the following:
This thesis research focuses on the negative effects that Concentrated
Animal Feeding Operations (later referred to as CAFOs) have on the
environment and the psychological and physiological effects of
alienation of food production on slaughterhouse workers of industrial
slaughterhouses in comparison to niche-market slaughterhouses....
Slaughterhouse workers are also at risk of Perpetration-Inducted
Traumatic Stress, which is a form of Post Traumatic Stress Disorder
and results from situations where the concerning subject suffering
from PTSD was a causal participant in creating the traumatic
situation.
http://scholar.colorado.edu/cgi/viewcontent.cgi?article=2157&context=honr_theses