There's a little inside joke within our hobby that complains about the over-abundance of "trading in the Mediterranean" games. To be fair to old Mare Nostrum, it also applies to Medieval Europe, trains, planes, and boats, etc. Of course, it's a stereotype exaggerated for humor. Nevertheless, shipping and trading have been and continue to be very popular and common themes. Did this mechanic start it all? Well, that's probably hard to confirm one way or the other. But I'm certain it has fanned the flames!