I've been thinking about this comment for a few minutes and do find it interesting. But the extremes of the comments and quotes above make it clear that even displaying your product is an ad; demonstrating how it works to a crowd would be an ad; telling someone that it exists would be an ad; there seems to be no way to tell the market that your product exists without that being defined as an ad.

So I would answer you with, given the extremes defined above, that indeed advertising is a necessity since good products would otherwise rot inside the inventor's home. It being illegal (say, for example) to have ads would mean that it is illegal to even tell anyone that you invented a product.

I think there's got to be some kind of give from the anti-ad side if we want to have _things_ in the world that do stuff - because if I can't even say "I made a better product that does x,y,z" then how the heck is anyone ever gonna find out about it? Where does the word-of-mouth kick off even?

You gotta _tell_ people you made something - but that's an ad.