Adding a physical address (i.e. ### street name) is already handled. But what about a business that uses a PO Box for its mailing address? Should ref=* be used? Put the PO Box in the notes field? I did notice that there was a addr:pob=* in the proposal section, but not implemented.
That’s an attribute of the business, not the geographical entity, so I’m not sure it should be on the map, only in some sort of business directory.
I suppose, but you also have a telephone field, website field, facebook field, etc. which could be said are attributes of a business. So, why not PO Boxes?
I normally put the business address obtained from that business’s own web site, while the business often physically resides in the city neighboring the postal address on the web site.
The standard address tags must reflect the true physical address, or you will cause severe confusion for anyone who uses OSM for navigation.
On things like website, for some reason people seem to like populating things about businesses, even when not the owner, but I would say it was mission creep. The only real argument for allowing it is that it tells you more about the nature of the business operating there.
I would generally seek to provide the number of the phone line physically associated with the address, even if the billboard gives the head office sales one.