Can A Business Survive Without Advertising?

I think we can all admit that in the world today not many businesses can survive without advertisement. Consumers buy what they know and they are not as likely to buy something they don’t know. One company that has surprisingly been able to stay alive with out Advertisement has been Krispy Kreme. They have basically survived on word of mouth, which is a rare occurrence. Now they are having financial trouble so for the first time they have decide to start advertising on radio and television. They are actually putting out a Valentine's Day commercial. They have not released the amount they are spending on commercial. My question is can a business in the year 2006 be truly successful on word of mouth alone? My assumption is no. I think this idea points out the important point that business must set aside money for advertisement if they want to succeed economically.