Daryl David -
I agree with you totally. However, the gap in visitor green fee revenue between what the top 30-50 courses in GB&I collect vs. what the next 200-500 clubs collect is probably very wide and is a big reason why many mid-tier golf clubs in GB&I are struggling to make it financially.
In this case, the 80/20 rule is probably more like 95/5, where 5% of the golf clubs in GB&I collect 95% of the green fee revenue spent by visiting golfers.
DT