If you follow your logic to its end it alsobis completely fine to roll coal and be a general piece of shit since it wouldnt actually change anything on a big scale.

Where do you think all those corporations get their demand and money from? If nobody bought any more meat the slaughterhouses would have to close down eventually. And sure, you alone wont be able to make any big changes overnight but if enough people do it at the same time you will have an influence on the market and governments.