Kids and Coffee

This weekend hubby and I did some shopping, as did most people it seems.  There was something I saw that I really don't understand.  We saw this parent who had several kids with her and she was scolding them trying to get them to calm down.  A few minutes later, we saw her at the Starbucks counter, buying coffee drinks for the kids.  If your kids are hyper and you are trying to get them to calm down, why in the world would you give them caffeine?  I don't have kids so I can't speak to what it is like to be a parent, but as a bystander, it seems very strange to give his something that will make them hyper when you are trying to get them to calm down.