Not so in fact, RAF Sealand was also in Wales!
And let's put the record straight on EGNR.
Hawarden village is a mile or so from the airfield up the hill and 'Hawarden' was the name given to the airfield by the RAF.
The main factory entrance on the south side of the airfield is right next to Broughton village so 'Broughton' was the name given to the factory site by DH, HS and then BAe, although 'Chester' has also been used by the factory over the years.
In recent years the airfield has changed from being a purely factory based operation to one which also supports a growing GA and business aviation community. It is this which has increasingly led to the airfield being called 'Chester.'
This is not new, however. Starways, Eagle and Cambrian all called the irfield 'Chester' when they ran the LPL - CEG - LHR service in the 60's. Note the designator 'CEG' which relates of course to Chester not any other local town or village.
Yes, the airfield is in Wales, just, but the nearest town or city of any size is Chester, in England yes, but in fact only a few miles away. Few cities in the UK have an airfield so close. So don't be surprised if increasingly the airfield is referred to as 'Chester Airport' because this makes sense commercially and geographically - people know where it is for a start, and can pronounce it!
Time to get over the English/Welsh thing here I think and wake up and smell the coffee, as they say. Airfields are allowed to change their names, you know!