It really is a problem for the depots, Avgas sales have dropped off around the country and if after 3 months you don't top up the storage tanks with a new load of Avgas it causes all sort of issues. If they are not selling enough to warrant a new load of Avgas then unfortunately more and more depots will remove Avgas altogether. I guess its even harder for the more remote airfields, I can't imagine a truck driver being real happy driving way out with only a few thousand litres of Avgas. I know if it wasn't for some depots selling 4 -5000 litre bulk orders then they would also be removing Avgas as sales directly into aircraft just are not enough.