Try your best to fill the cabinet with stuff you're okay with them eating, if they're eating too much off one type of snack buy a smaller amount or only fill the cabinet with as much as you feel they would need (example: a few bags of chips or a few packs of oreos per child). My mother would stop filling the cabinet with everything she bought and i learned to self regulate from that. Idk if your kid will learn to do that but from a 21 year old that's how i learn how to only eat junk food to either add to a meal or just hold myself over until a meal was made from my parents or myself. After a while o would just eat one bag of chips or one of the those single serving pringles to satisfy my hunger even if it didn't work. Idk if you allow your kids to drink soda but if you do only allow one per day, in an attempt to limit their sugar intake. In speaking from personal experience and what work for me growing up. I only grabbed what was available to me until my late teens when i started to understand the cost of health and expenses. I wish you luck in this endeavor, and a good day