Serious question. Do other countries - particularly with their own Monarchy - call our navy "The Royal Navy"? If it's just a British colloquialism then it will indeed be for marketing purposes!
I invented something pretty pokey over Christmas. Basically a triple of Tesco's Finest Salted Caramel Liqueur (think Bailey's with extra caramel-ness and a really, really small hint of salt) with a single shot of dark rum. Tasted like a liquid, alcoholic Mars Bar. Not recommended during marathon...