According to JEI/EMI the Database block can be crafted with either a Plum, a Royal Jelly or a Chest in the Bottom Center grid Square

unclear if this is by design but seems too varied to be the case, why a plum?

This was intentional. It was written by the same person who originally wrote the code for the database.

Ah that's fair enough then, it just seemed a bit weird to be a chest, royal jelly or specifically a Plum

I'll close this as it's not an issue