Only accusing the "big companies" for doing all sort of "unethical" things, is like only accusing mass murderers for the killings that they do. Every crime is a crime. Big or small. Small companies do similar shady practices and abuse people or destroy the environment.
But best is to look at the system that creates these entities instead of accusing companies or people.
As long as the underlying practice on this planet is to TRADE or else you are fucked, then this is what we are going to do and prioritize. Thus the evolution of companies and billionaires, waste, pollution, you name it.