The Frome Hoard has been put on display in the new Somerset Museum. See
http://www.culture24.org.uk/history+%26+heritage/archaeology/art365271
The Hoard was purchased after a successful fund raising campaign. Other, less significant hoards are typically returned to the finder who can keep them or sell them ultimately to collectors who then will have a coin with a known provenance to add to their collection. Is it really necessary for the State to retain everything?