I've been thinking about the old Nestlé boycott, which started back in 1977. To review:
Nestlé was pushing its baby Formula as an alternative to breast-feeding in poor countries. There are three reasons why this is harmful:
1) It's a powder which must be mixed with water. Breast-fed babies are getting exposed to contaminated water, common in these areas, which leads to a host of diseases, and of course babies are particularly vulnerable to things like diarrhea.
2) Poor women are watering down the formula to make it last longer, so babies are malnourished.
3) Breast-fed babies get antibodies through their mothers' milk.
-- (source: Wikipedia article)
Yet I see the boycott is ongoing. I'm not saying one should throw in the towel on causes that are a long uphill battle -- otherwise we wouldn't have a black man running for president in the U.S. -- but if the Nestlé boycott is typical, then signs suggest that boycotts are mostly useful for salving your own conscience ("I'm not supporting something I think is wrong") rather than for changing corporate policies.
The fact is, companies pay less attention to what people AREN'T buying than what they ARE buying.
So, since many people are now going to Trader Joe's or other sources to buy organic, that's something that can be statistically traced. Lo and behold, more and more "certified organic" items are appearing in grocery stores... because companies go where the money is.
Similarly, once a significant chunk of consumers started buying hybrids (I'm proud to be one of 'em), auto makers started getting on the Green Machine bandwagon not so much for the environment, but because they realized this could be a profitable niche market. Now they're competing with each other to produce the most fuel efficient vehicles, get hybrid technology into SUVs, and come up with new alternative fuel technologies that the consumer will be willing to shell out more money for.
It makes sense. It's much harder to track the reasons why people aren't buying something than it is to track what they are eager to buy. American consumers are now eating a lot more sushi than they did, say, 30 years ago. Who knows why, but there it is: more people want sushi. So there's more sushi restaurants.
People who are outraged over something and thinking of boycotting it should try and think of an alternative product to buy that telegraphs, loud and clear, what their preference is.
As a side note, I don't think that companies or politicians pay much attention to online polls and petitions. I could be wrong on that, but I believe they still brush those off as a) a limited segment of the population and b) easier for individuals to create phony identities and vote multiple times. I'm not sure that stacks of written signatures have much more weight, but at least it's hard to ignore crates being dropped on one's doorstep, or the mail being filled with thousands of postcards.