My Dad is always pushing food on me. He'll offer me something, I'll say no, then one minute later he'll offer me the same thing again or something different. There are several different factors at play here--1) he's been diagnosed with a B12 deficiency, so in some cases he just doesn't remember that he just offered me food and I said no, 2) he spent most of our childhood trying to ignore us, so sometimes when he asks a question of me, I think he just "forgets" to listen to my response, and 3) he's half deaf but won't admit it, so sometimes he doesn't hear my response but pretends that he does and 4) he's trying to show me he loves me by offering food. I'm sure that he's not trying to sabotage me (he's really very impressed with the changes I've made in my life), I think it's just that we have a difficult relationship and he just can't think of anything else to say to me.
Unfortunately,
Dagmar, having the conversation you had with mom just isn't possible with my Dad. Between the memory, the listening, and the deafness issues, it's virtually impossible to have a conversation with him about anything. So usually what happens is I put up with him until I'm really annoyed, then I explode with something like "Dad, I used to live here. I know where all the food is and I'll help myself if I want anything! Stop offering me food!"
That works for a little while. He's usually amused by it.
Luckily, he lives 2,000 miles away from me, so I only see him once or twice a year.