NRO> Might be useful if, for example, a family were visiting a NRO> large park or festival and the kids wanted to do one thing NRO> and the parents wanted to do another.
Very useful for backpackers or cyclists who travel at different paces. Or, for packers who go into an area on different dates and don't want to be locked to a specific meeting place (or just want to know how far away the other party is).