Stores gets cleared when the cache is deleted even if read only

When I branch one sql table to a persistent SQL table store cache in Infinispan, even when the cache is read-only=true and shared=false, if the cache is deleted the SQL table is cleared (table exists but all the data is gone). If the cache is not read-only this is also the behaviour, so there is no difference between read-only true or false when dropping a cache. I would expect that if a cache is removed, the data in the SQL table to remain the same at least in the read-only configuration