Not to suggest postal_code on nodes

[Davileci]

When tagging places and applying optional presets, Vespucci gives the key postal_code to tag; however, this practice does not fullfil the Karlsruhe Schema and is not allowed according to the wiki.

[davidpnewton]

You'll run headlong into the French on this for one. There seems to be a really weird consensus that sticking address tags on nodes corresponding to the locations in the BANO database that the French OSM community has put together is a good idea, even when the BANO database clusters all of the address locations for a street together in one place utterly nonsensically ….

You'll quite frequently see address nodes simply created by what appears to be importation in French towns, cities and villages with little to no care taken over whether the locations actually make sense. Then there's the divorce between buildings and addresses. If there is a house on a street with a number on it then the postal address is for that building, or part of that building if it's something like a block of flats. There's an argument to be made that the postal address might be added to post boxes if those are separate from the building at the end of a drive, but again that doesn't correspond to the BANO locations.

Beyond the French you'll also run smack into POIs for shops and entrance nodes for things like maisonettes and flats. Those have address information on them and therefore can and do have post code information on them as well.