I don't have DC but when I was younger my brother has severe asthma and eczema and a cows milk allergy so he could never have chocolate and although I had it, not as much as I maybe wanted to. My mum used to give away or throw away a lot of our Easter eggs! Carob isn't the same and is vile.
However that didn't stop us from the age of being allowed to go to the corner shop (6 or 7) buying half penny and penny sweets, and yes, chocolate even my brother. We also used to go to an old fashioned sweet shop with glass jars run by an old man.
My mum's other main reason for keeping us away from sweets was because she was fed them as a child and as an adult had lots of expensive dental work. She remembers pear drops with chocolate or toffees...!
We did have apple crumbles and pies homemade by my mum, lemon meringue pie etc but these were either desserts or treats. She also made Queen Cakes quite often which are fairy cakes with raisins/currants in but with brown sugar! Her favourite chocolate was Frys Chocolate Cream and Mars Bars and After Eights.
As far as I know we rarely had fruit juice if it was it was orange juice or orange squash and no fizzy drinks apart from special occasions - parties mostly.
I agree grandparents will and did with us ply us with sweets and chocolate in secret.
We do have good teeth now but my mum was obsessed with us brushing teeth. And when you get to teenager stage you tend to rebel and eat/drink what you like, slush puppies, ice pops etc!
Neighbours children (toddler and 5 year old) are rationed sweets on a daily basis and this certainly makes them sugar mad when they do get it. This time last year I came back from holiday abroad and brought them tubes of smarties with car/princess toy on top, the mum had to go and visit her sick father so the dad was left with the kids alone. I saw him after a week asked if they liked their toys, he said they'd gone through the smarties like mad and when they were put away or gone had stared longingly at the cupboard where they'd been kept! 
I think little and in moderation including fizzy drinks and juice. Allow the odd fizzy drink occasionally or they may get offered it at a party but at leafs if they try it they can decide whether they like it or whether it's the Devil's own drink!