The map is not fooled by Polyjuice potions, Animagi, invisibility cloaks, etc. Why is there not widespread use of maps like these for identification/security purposes?
We know it is possible to infiltrate, for instance, the Ministry of Magic using these methods. However, a map of the Ministry (or at least the entrance) would give a guard perfect information about who is coming in and out, rendering most obvious disguises useless.
Another one is, when the snatchers (or Death Eaters) were hunting the trio, why not enchant a map of a given area to see if someone with their name was there? Even if they will search the area anyway, it would help verify anyone they catch is who they say they are.
I initially thought the Marauder's Map was unique to Hogwarts, but I recently read it was was created using a Homonculous Charm (see here and here) The spell does not sound particularly unique, so I get the impression it can be cast on arbitrary maps. I've been reading other answers to similar questions, and while everyone agrees it was very clever (even genius) magic, nobody says the spell cannot be cast on arbitrary maps.
Anyway, it sounds it could be used as a standard method for identification (at least passing the Marauder's Map test could be a minimum requirement). Why is that not the case?
I'll agree it is a given that the spell is hard, and thus most would not bother with it. Also, as pointed out, since it is primarily a tracking it is probably not considered when planning security/identification. And if it was, I think the conclusion that most people would object to something so invasive is reasonable.
I still think there is a lot of room for using and abusing the map. Are there radar/tracking tools more powerful than something which can accurately track and label everyone in a given area, regardless of disguise? It probably has limits, but it doesn't appear that way from the books. I think the Marauder's Map is not unique, but I'll accept the answer below as to why its use is not commonplace.