Hey I totally understand! Its tough watching my kids even eat tons of carbs all the time and they are string beans! I was NEVER a string bean in my life!
My husband is the same weight as when he was in collage.
His sister is exactly the same, she can scarf down pancakes etc
and ti doesn't even bother her one teeny bit. Tall thin and musculed both of them! Its not natural I tell you;-)

Tell hubby to quite nibbling your snacks or just do what I did,
buy extra of everything because I found my kids ended up eating more pork rinds than I do!
Strange how different people react to different foods.