While you have grasped the concept of a town including the name of a local feature to better convey location am afraid it dies not apply in the case of Dunree.
Think the name concept dates back to when rivers were the highways and knowing both the town and river it was located on was more important. There are two Newcastle’s in England so knowing which river the town is located beside is still useful today.
Politics can also play a part. Recently Stains which is a suburb of London renamed itself as Stains upon Thames. This was done in an attempt to move the local identity and hopefully realestate prices upwards
As for Dunree this is purely my use of words. At best Dunree is a few houses that are located next to Lough Swilly. I do not think that even after closing time on a Saturday night that anyone would refer to it as Dunree on Lough Swilly.
Not forgetting that Donegal is the equivalent to a state. The one where all the Irish wish they were from however only a select few can claim the title........

