My kids also say the cold pack cools down the thermos. They really like the food in the thermos to stay hot and they claim it does when there is nothing cold in the lunch sack. I too prep it in the morning by pouring boiling water in the base while I warming up the food.
" I object to violence because when it appears to do good, the good is only temporary; the evil it does is permanent." Mahatma Gandhi
"This is the ultimate weakness of violence: It multiplies evil and violence in the universe. It doesn't solve any problems." Martin Luther King, Jr.