Possible Clues:

• Diners' requests
• Takeaways from restaurant in the boxer's suitcases?
• Diners' requests, sometimes
• Containers for leftovers
• Carriers for leftovers
• Child's pet checked by security at the airport for the scraps coming out of restaurant
• Some restaurant containers
• Takeaways that might spoil the canines?
• Leftovers packages
• Boxer shorts, for example? People remove them after eating