I'm gobsmacked by a lot of this. I work in a primary school. My main role is as a lunch time supervisor. Both my children also attend the school.
We don't have a strict policy but there is a lot of advice on what not to include. Only fizzy drinks and chocolate and sweets are outright banned.
A number of children have got the worst lunch boxes. No sandwich or pasta, just cheesestrings, dairylea dinners, crisps, chocolate biscuits and a Capri Sun or similar. It's not one or two, it's loads.
We have a number of SEN children, their needs are taken into account, both with their packed lunches and school meals.
In terms of school meals, they only get milk or water to drink. There are numerous options which are pre ordered a term in advance. Every day there is a choice of fruit or yoghurt and a pudding, always low sugar, usually containing fruit.
Whilst we never force any child to eat anything, we encourage them to try things and don't let them just tear into their pudding without giving their meal a go.
Someone upthread said she didn't want to be restricted when packing her kids lunch box as they weren't overweight. Believe me normal/underweight children can be very unhealthy too.
In some of our worst cases, we have children coming in with a tub of Pringles or a 5 pack of cake bars, as their whole lunch, every day.
We have a no sweets/cakes for birthdays too, but have the occasional bake sale.
The idea that a chocolate bar/crisps every day is ok is ridiculous.