Do fast food places count? Since I was 16 I've refused to eat at McDonald's, Burger King, etc. because I found out that rain forests in South America were being slashed and burned to provide the cheap meat for the burgers. I found out that the indigenous people basically died because they didn't have their habitats anymore.

I couldn't partake of such violence.
There's a whole list of Chinese restaurants in Chinatown in New York that I refuse to go to because they refuse to recognize thier workers' rights to form a union. Then there are restaurants in the Bay Area I won't go to because I don't like the way the waitresses yell at me. Any Chinese Americans out there know what I mean?