The weird world of sugar free sweets and VAT

It's the time of year when my distributors have lovely new catalogues with the latest ranges of sugar free sweets. I have been trying to decide which new products to stock.  I can't help wondering why the powers that be complicate things so much.  In theory VAT should be a fairly simple way of taxing things but it isn't.  

It probably sounded right at the start to say that food should not have VAT charged on it unless it was being purchased in a restaurant or cafe.  The problem then was to define "food" for tax purposes and that is where it all got a bit silly and confusing. 

Sweets and Confectionery in general have VAT added so most chocolate has VAT on it. However there is no VAT on a piece of chocolate that is sold as a "melt" to be made into a drink by being melted in a cup of hot water or milk.  Seems illogical to me.  But a logical system wouldn't charge VAT on a biscuit coated with chocolate on both sides when choc chip cookies, chocolate filled wafers and double coated biscuits all have no VAT on them.

A cake can have chocolate on it, under it and inside it and still not be standard rated.  

Finally,I do wonder if anyone can explain to me why chocolate body paint should be zero rated, when cough sweets, sugar free or not,  have VAT charged.