I am posting for friends who are arriving next week in London for a week with their 4 adult (college age) children. With the cost of an inexpensive lunch running $20 and assuming dinner can be gotten for the same and adding breakfast, they are going to be close to $2,000 just for food cost and that assumes they won't do any nice dinners.
Please provide some unique and unusual ways to survive (they are willing to pack picnics). Their hotel may have a small kitchen for eating breakfast and packing lunches.
They are staying at Marriot West India Quay, 22 Hertsmere Road, Canary Wharf
London, England E14 4ED