Basically, they should prohibit parents who don't pay attention to the proximity of children to hot liquids.

A previous partner of mine told me of an occasion where an infant daughter of his (for whom he did not have custody), pulled his cup of tea from the coffee table in front of him and burned her face and chest. He felt that his partner, who yelled at him for his inattention, was wrong...

I can see why public places would want to minimise the risks though.