Just to add that if you have some time in Caen this is a really useful retail park - a number of restaurants including one of the la Cree seafood chain and a massive Carrefour for last minute wine shopping. It's a bit of a hike from the port (there's a more convenient hypermarket at Ouistreham if you are staying at Capuchines or Riva Bella) but worth a look if you've got time on your hands.
For wine we always use Normandie Wines at Ouistreham port. Lovely people, we leave them our order from previous years and let them know when we are arriving and there it is all boxed up, they even load into the camper van and allow us to leVe the van in their car park while we get something to eat from the restaurants just by the port. The wine is good and cheap, everyday drinking wine and the average price per bottle, even this year worked out at around £3.67 per bottle.
Marvellous!