There is no obligation on a licensed airfield owner to accommodate any outside traffic. Hawarden and Chalfont are good examples and I'm sure there are others. Just because the airfield owner happens to conduct activity at its airfield which requires it to be licensed does not oblige them to let all comers fly from their airfield - and some don't. I don't know what policy ISSCo adopts, but it is not a foregone conclusion (as suggested earlier) that a licensed aerodrome has to allow anyone in (except in an emergency) as has been suggested.