That's the thing too mama all children are different, what you might get away with with one, you won't with the next.
I have a full compliment of children of varying ages. 
Although DD has her issues around her teeth/food and so on, none of the rest have any fillings - so it obviously isn't ME, but you would only know that if you knew me.
The thing that really really really gets my goat is the assumption, like LOTM made that it must be squash/sweets/crisps and so on.
I know we were massively judged for letting DD rotten teeth and all, have coke on a family dinner out with my in-laws. It was my BIL and his wife who were very vociferous that she should have diet as with the state of her teeth it would make her teeth worse to give her full sugar coke.
I was fairly full and frank in my explanation to them. 
Thing is, we'd brought all her food with us, she was 3, she couldn't have the same as everyone else, she had to have special stuff, she couldn't have the chocolate profiteroles, or the lovely sausages and chicken nuggets, or the gravy with the roast - giving her the same kind of drink was the only way to make her feel a wee bit the same as the rest ?
Does that make sense?