Snacking is normalised and I would even say encouraged from the earliest age. Babies can't walk or talk but are already eating baby crisps or melty puff or rusks or cereals bars. People eat all day long. People eat in the street, on buses, People carry food with them wherever they go, in the car, in handbags. It is so weird.
We don't serve morning snacks. Breakfast, lunch, if a child is young, there might be 4 o'clock snack after school but always eaten at the kitchen table, not in front of tv, or bedroom, and then nothing till dinner around 7.30-8. French kids survive surprisingly well the lack of crap and are the least fussy eater I can see.
It is an Anglo-Saxon culture thing, UK, US, AUS. The snaking, the takeaways, even the word "treat" , the lunch combo with a soda +crisps+sandwich and they can't see anything wrong with it. So don't worry about the comments, @Catkitkat . It is hard in the younger years, when the kids see crap and it is highly palatable and addictive crap. Both for kids and many of the adults. So no, you can't give free rein , because this junk has been engineered to be irresistible.You are a parent, you teach good habits for life. There are sometimes food. Not daily, not weekly. There are however ways to include them in your life
We used to do the book marathon. We would go to the library, take the maximum amount of books allowed on each card. , go to the lollies shop and each kid bought a bag, and then we would spend 5 hours on my massive bed, the kids eating the lollies whilst I was reading them the books after after the other. So yes occasionally, as part of something. A luna park trip, A cinema. A special occasion.
Good luck!