Junk

 Washington Post: Smuggling 20 Diet Cokes? The junk food Americans can’t travel without. Snickers. Skittles. Vegemite? Comfort food is essential for frequent fliers. By Heidi Pérez-Moreno

She brings a suitcase full of Diet Coke, and as her trip goes on and her inventory wears down, she collects more space to fit the trinkets and items she buys from her travels.