I am on record as being skeptical of the notion that if you shop very carefully, you can make society better. "Conscious consumption" is not a tool for structural change, and any election that requires you to "vote with your wallet" is always won by the people with the thickest wallets (statistically speaking, that's not you)...

Now, that's not to say that boycotts are useless. But a boycott is a structured and organized campaign.