which should primarily be a light aircraft VFR service
Stop and think for a minute about who actually pays for this service. I'll give you a clue, it's not light aircraft/VFR traffic.
Not all airfields have digital atis, therefore ACARS can only give you a MET. Not much use in working out which runway is in use if the wind is VRB, hence the need to speak to someone to get an airfield actual.