Just a question: are crafts not rendered at all in the default mapnik style? I added a craft=shoemaker (which I think is the correct tagging for a cobbler who only repairs shoes and does not sell new shoes) and there is nothing rendered, not even a name (except for the addr fields):
https://www.openstreetmap.org/node/2925015923
Whereas I also entered a shop=fishing which does get rendered as a dot (I assume there is no specific icon for fishing shop and a dot is default for all shops that have no own icon):
https://www.openstreetmap.org/node/2925016988