I must have missed this the first time around. One challenge is that a lat long does not uniquely define a location. To do that you need to also specify a spheroid. There are many different spheroids in use, most often WGS84, but not always. As web technology is often abused for other uses than originally intended, not specifying a spheroid might not make much of a difference to someone trying to locate a restaurant, but in other fields a mistake in the spheroids-used can have expensive consequences. There are examples where wells have been drilled outside of the area licensed for exploration, with the company forced to drill another well inside their licensed area in order to meet a work commitment.