Does anyone know why meals recipes often call for sugar?

For instance in tomato sauce based dishes?

This puts me off and i have never tried a recipe like this.

Does it have any reason, change any taste or anything?

apologies for double thread, not sure how that happened.

Like all alchemy it does something to the overall flavour as sugar is well known to bring out the flavour. Tomato dishes are particular flavoursome with a little sugar.

Canned tomatoes in particular also need a lot of sugar as they have a high acidic content and you obviously need to sweeten these down.

Sugar is also used to create texture in dishes.

I don't use cane sugar in my main dishes. I might use honey as a meat tenderiser or for a glaze.

I went to a friends house for dinner once and I saw them putting sugar in a tomato soup, I thought they'd gone mad

Not a bad idea to put a teaspoonful of honey in any savoury dish. Also a square of chocolate can add a certain nuance. Suck it and see.

I always leave out the added sugar, its bad for you

Salt is the same, I always add a bit of salt to chocolate recipes.

I have stopped buying the occasional cheese scone as they always taste as though there is sugar in them!

As Stud u like says, the reason is to counter acidity. You know that kind of 'raw' taste you get from tinned tomatoes straight out of the can? A spoonful of sugar (along with salt and garlic) counters that and turns it into a nice mellow tomato sauce. The sugar makes a big difference.

I would often add sugar (or a sweet condiment like redcurrant jelly) to a meat stew or gravy that has been made with wine that is very acidic.

Also good if you are making a dish with lots of chillies. A little bit of sugar takes away the bitterness, leaving just the heat.

Quite right too! I always use a bit of salt in sweet recipes.

Heston demonstrates an interesting property with salt, he adds it to tonic water in increasing measures and at a certain point it will taste sweet. Too much of course and it will taste salty

Brown sugar adds a nice depth to savoury items