Hobnob biscuits are native to Britain. GingerNuts too. Oreo biscuits are native Yankee biscuits: they have more cookies than GingerNuts. Gingernut biscuits are usually left behind after use and do not age well. Gingernut biscuits have a short shelf life. Usually,when a better biscuit is found,the gingernut finds itself alone. There are organisations that cater for broken gingernuts,but a fractured gingernut is a broken gingernut. It cannot be put together again. A native Oreo biscuit will oft find its way to the top of the biscuit tin, but how it does this is still 'unknown' and requires further study.
Oreo nuts(or biscuits as they are known in the UK),are often the favorites of George Clooney,Leonardio de Caprio and other Hollywood royalty. They should not be confused with the British ginger-nut. The British ginger-nut comes from an olde line of biscuits whereas the Oreo is a much recent American invention.
Once past its sell-buy date the olde Britsih gingernut is usually discarded. Its shelf life can be extended by judicious professional help,but when its broken it usually goes to the back-of-the-larder to be forgotten.
The outcome for the Oreo is usually much brighter tho. It goes on for years,its shelf life extended thru commercials and its current appeal.
For further information and references,see Biscuits: Now and Then. British and American tastes.
The book is currently on demand and awaiting a re-print.