My caterer ate the food

I had a small wedding rehearsal for my son catered. My first time hiring a caterer myself so not sure of the etiquette. Based on the menu of salad, shrimp cocktail, Brunswick Stew & grilled cheese, they said they would not need arrive too early to get everything prepared & they arrived about 2 hours prior to the 5:30 seating time. Everything was ready on time & delicious. My question is I came into the kitchen during the meal to grab the champagne for a toast & the entire crew of approximately 8 people were standing in the kitchen with loaded plates eating the food. At the end of the night, I was told the leftovers were in the fridge but there wasn't much because everyone (as in my guests) ate so much. I did not reply to that at the time because I am not sure if it's normal & expected that the Catering crew is going to eat your food or not. I would expect it if it had been an all day affair, but from arrival to cleaned up & gone was a total of 4 hours. And I would not have batted an eyelash at snacking on the food but they all had loaded plates & then blamed lack of leftovers completely on my guests as if the 8+ people they fed had no effect. If this is normal, I'll let it go but it's really bugging me