You are talking about a very grey area.

Although not Ireland, but in England I was with Fay Godwin back in the 1980's on a workshop, we were all making images at Chatsworth, a British Stately home, she shot one of her well known images, it was of a statue of a lion, just outside a tea room.

She'd paid to enter just like the rest of us, it never stopped her using & publishing the image for exhibition or in a couple of books

She had no problem with this image and on my wall is another well known image also taken a year or so earlier at Chatsworth by Peter Cattrell of a Giant Hogweed.

I photograph historic sites in various parts of Europe and where there is a will there's always a way.