I understand what you mean, but I would modify this statement a bit:

There are no successful economies without information exchange. Discovery can happen without advertising -- if you consider that the main feature of ads is that it's unwanted information distribution.

There is not any real-world economy that has implemented that information exchange in the absence of activities that would be accurately described as advertising.

Even thousands of years ago in illiterate societies people would advertise their goods/services via verbal campaigns, drawn pictures, songs, etc.