Sort:  

This is not possible and will not be added, as it could cause issues with people abusing it on one hand, and the map filling up with the same posts multiple times, which might give a bad browsing experience!

It seems natural to use multiple geotags in post that describes many places (f.e. in https://steemit.com/travel/@miosha/land-of-extinct-volcanoes-part-7-16-milek-quarry-cf4561ff483f8est I wanted to pin start of official trail around the mountain as well as shortcut leading directly to the quarry).
I don't see how it prevents abuse either, if one could just make multiple posts composed of geotag + link to main post, but ok.