Im using google places autocomplete on my website. Users can enter any address or place and select from the suggestions below in the form. When users select a suggestion more details about the place are downloaded such as latitude and longitude and further used in the process. This is how it currently works and it works well.
Your taks would be to make sure that users can enter any place of interest such as for example: Big ben, Eiffel Tower, Brandenburger Tor, or the name of a bank, amusement park or anything else that is not an address or specific place.
Whenever users select such a place of interest (POI) then the additional information (such as lat, lon) should also be downloaded as the script currently already does for addresses and places.
For devs with good knowledge of this google places autocomplete API it should be very simple, it is probably only a matter of adding a line here and there.