That greenwashing exists is a good sign for the environmental movement, because it means being green is becoming important to consumers.
However, greenwashing itself is clearly a bad thing. When a consumer buys a product which he believes is better for the environment and later finds out was just a case of greenwashing, it's disillusioning. People then become less likely to buy green products for fear of falling prey to the greenwashing illusion again. A couple of recent studies have shown that consumer confidence in and willingness to pay more for green products is declining.
"According to a green survey from Rackspace Hosting (PDF), 44 percent of respondents are willing to pay more for green products and services this year; down significantly from the 59 percent of respondents that were willing to pay more last year.
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“It’s interesting to see that customers still think green is very important, but today they may be less willing to pay more or trade performance for lower carbon emissions."
"The problem, he said, occurs when marketers make exaggerated claims about a product's attributes, which may be fine when selling toothpaste or vacations. Most people probably know that the toothpaste won't actually make their teeth sparkle or help them get the girl, but they play along with the joke. But when an advertiser says its product will actually ''improve the environment,'' or some variation on that theme, savvy consumers recoil, Lawrence said, knowing that, in all likelihood, what is actually meant is that the product is only less bad for the environment than it could be, or than competing goods. ''This can really backfire with environmental advertising,'' Lawrence said."
So I think greenwashing, while indicative of the strength of the movement, itself is bad.