We used to store enough in our fridge for two blokes to last 4 days on the beach however we never used to take half the crap most people take and we'd pack differently as well. Beans, bacon, beer, butter, meat and milk, but we always cycled our fridge stuffs, i.e. 8 cans always cold and the rest outside the fridge, enough long life milk for brekky put in before bed the rest stored. Meat pretty much stayed in all the time but butter rarely did unless it was really hot and whenever you got a beer out you put another one in.
We take the same approach to fishing, we can cart 4 surf rods and enough gear to fish with down the beach with two people and a single trip yet most of the people we fish with take several trips because they take all sorts of unnecessary shit like tackle boxes, camp lights, bags, seats and all manner of other shit. We just rather do things easy with the least amount of packing, unpacking and loading.
We just brought one of those cold boxes (the ones that with the right ice packs last 15 days before the ice melts) and for us it's 60l capacity is huge because we are used to minimizing and adapting. Sure we could fill it if we wanted too but we've always taken the attitude of less = more and learning to pack efficiently is better than just filling the space you have.