Don’t leave your nuts out to be grabbed by any and all. Problem solved.
It’s her home. Does she have to keep everything under lock and key under her own roof? How would you like it if your maid/cook/gardner/handyman helped himself to your stuff? Or maybe because the Queen is rich she is therefore not entitled to the common decency everyone else can expect? Maybe it’s OK if the help pilfer her light bulbs and toilet paper too?