Inexpensive play food sets (for play kitchens) come with 100+ pieces. Unfortunately, 1/4 of them are cheap cardboard boxes that typically last no more than a few days before the child tears, crushes, or otherwise mutilates them.
Take bits of newspaper and stuff those boxes till they're fairly rigid. Then take clear packing tape and seal them up all the way around. Seal the paper labels on the "cans" too by wrapping packing tape all the way around them.
Your child will get to make-believe to his/her heart's content!