Actually, I do believe that it's an important question nowadays – what products should be given to children in canteens? I remember me being at school. What could we get in our canteen? Br-r-r-r... don't ask me, I don't remember because neither I nor anybody I know ate it. By the way, we also could BUY there some juice, “pizza”, curds, yoghurt. Some pupil really bought this staff, and to be honest, I was one of them. But more often we spent our break to pop into a grocery store and buy some snacks. So, it's not a surprise that a great deal of pupils got gastritis.
So, during school years a better part of all pupils is likely to get this or that gastrointestinal disturbance. How to solve this problem?
The idea not to give children butter, salt and sugar could came only to a person who hates children (excuse me my rudeness). This can only make the situation worse – more pupils will prefer to buy chips and cola.
I see only one solution – to make school food more delicious and at the same time healthy enough – give children fruits and juice, milk or yoghurt, vegetable salads. But it is too expensive, that's why schools can't afford it. But may be it's better to spend money not on new plastic windows but on food for children? It's awful when one begins to economize on children's health.

Now our government is trying to solve this problem somehow. Pupils are given juice twice a week and yoghurt once a week. The food is healthy. The funny thing as that only half of the week is provided with food. but it's at least something.
As for salt, butter and sugar - well... They are not harmful. They are even necessary, but only in small quantities.

And can any substitutes be found?

I think that the very problem is the sum of pocket money of a contemporary child. The parents should somehow limit it somehow, but they sometimes think that the more they give the better they are. So a child may afford 2 packages of chips, 2 bottles of coca-cola, 3 bars of chocolate and it can really cause some health problems.

Maybe. But salt, sugar and butter are necessary in normal food. It's a fact.

Maybe, supplying schools with healthy food is too unprofitable?

It's rather strange because children need enough salt, sugar and butter for juvenile growth. Of course, putting too much sault and sugar in food and eating too much snacks and sweets are bad for children. But it's important to think about people's health and make reasonable decisions in this case.

I don't see anything harmful for a child to a eat a bun or a sandwich with butter on it. But it seems reasonable to cease selling crisps, salted crackers and gas water in school canteens.

It's nonsence! How is it possible to leave children without salt, sugar and butter? Of course, excessive salt intake is harmful, but this excuse seems to be thin!

I choose salt and sugar in normal food!
Most dishes are unpalatable without salt. As for sugar, brain requires glucose for fuel at every second and children have to think a lot at the lessons.