Also, vibram is an established brand; I have horribly flat feet and prefer large and heavy boots with industrial-strength arch supports over running flats, but when I go to buy boots, I look for the yellow vibram logo. I don't think I've bought a pair of boots without vibram soles in the last 10 years. The idea is that they don't need to use shady marketing practices; they have a good reputation and innovative products.
If I like the product and people ask me about it I don't mind evangelizing it. However if so many people ask me about it that it becomes a burden I can see why people want a little love back.
do you think Herbalife is not shady? I think the shady part of herbalife is the MLM, not the placebo they are selling. GNC sells plenty of placebos, and they don't seem to be shady.
I guess it's a matter of opinion, but it seems to me that if you have to pay for good word of mouth, then maybe your product isn't so great after all.