So she seized the opportunity to stock up during an official visit to Waitrose with her husband Prince Charles this week.
And the heir-to-the-throne no doubt applauded his wife's good taste. The majority of the items in her £28.49 basket of goodies were from Charles' Duchy Originals brand.
The royal couple's visit to the Belgravia branch of the store, to mark the supermarket chain's exclusive deal with Duchy, was the start of a busy day.
After the shopping spree they headed to the Kids Company charity in Lambeth, South London, where the 62-year-old Duchess proved herself to be something of a ping pong pro.
She challenged ten-year-old Emmanuel Theophilus to a game of table tennis and defeated the youngster, even though he gave it his best shot.
"She was brilliant," he said afterwards. "I was playing my best. I would challenge her to a rematch because I think she won."
Not one to miss out, the prince, 60, also accepted his own challenges – one to a game of pool from ten-year-old Kiya Medford, and another to take on the job of goalkeeping in a table football match.
"I don't think you've quite got the hang of it," Camilla quipped in response to her husband's yelps when the attacking team came close to scoring.
Finally the pair travelled to the 999 club in the south east of the capital, which offers help to the homeless.
Camilla's sense of humour shone through as she held aloft a bag decorated with the motif: "I'm an old bag from Deptford", given to her during the visit.