Two steps forward, one step back...

So this past weekend I spent Saturday night at my mother's house. She was in and out all afternoon.
She has a lot of non-Core foods in her house. Most of it I could care less about. And honestly even the things that caught my attention there would not catch my attention anywhere else. Like chips. I pass by three or four vending machines full of chips at work every day. I go to the grocery store at least once a week and pass by chips every time. They don't appeal to me at all.
Yet, do you know what I found myself doing? When I thought she would be out of the hose long enough to get away with it, I'd go to the pantry and grab a few chips. I was not eating out of stress, I was not unhappy or nervous. And Lord knows it wasn't eating out of hunger.
It was the secret eater, the girl who got fat before her mothers eyes though her mother never really saw her overeat, coming back to say hello. I used to sneak food growing up all the time.
The thing that gets me, is that now, I don't think my mother would really make any big deal about me eating some chips if I chose to. She knows I'm dedicated to working my plan and would know I'd account for the points (which I did). So why did I feel I had to sneak it?
I live by myself, 45 minutes away from my mother. I could eat McDonald's for breakfast, Wendy's for lunch and Sonic for dinner, every day and she wouldn't know. But I don't do that! So why did I have that urge to do it at her house? I'm not sure at this point I have that entirely figured out. There's something else to keep mulling over...