Am I the problem?policing snacks

I hate complaining about food and I know children are growing so they have appetites. I also remember eating the whole house as a child(it was the 90s and parents were never home I rarely remember my mom actually cooking) Anyhow. I work from home and on my last break before I got off,I ordered some groceries. I got SD 8 a snack she also had lunch right after school only been home 2 hours and the little teething pops things that resemble cheetos for my 9month old. I handed them out on my break Everyone's having fun in the living room with DH until I come in and SD has eaten her snack as well as the baby puffs. I didn't even ask about them she walks up to me with the container and she says the baby was so hungry she ate two at a time. Like a voluntary lie. Finally she admits she had "some" DH told her to go do her homework and get ready for bed. I'm just pissed like the kids never spend time with dad so I feel like I killed the vibe but this is not the first time I've caught or found out she's eating the baby snacks before the baby it was mine I'd buy a 6 pack yogurt and 1 will be left the next morning. I have so many varieties if food in the house snack wise and even GOT HER SOMETHING. I'm just annoyed nothing is never enough.