Word of mouth is the most difficult and misty effective marketing. When people think of vaporizers the name that typically comes to mind is Volcano. I'm pretty sure that was musky obtained they word of mouth.
I would say that the grocery business is a different business model - and it's "success" was not by word of mouth. See the GINORMOUS signs out on the streets in front of each grocery store. That's called advertising. Most people are generally going to go shopping where it is most convenient. In Whole Foods case, they have an organic theme/niche; which was partially by word of mouth - but they got plenty of publicity thru media outlets and didn't have to spend lots of advertising dollars.
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