Her being the baby for 5 years didn't help any either. So now anytime we go out, she expects something. It took me about 8 months to get her from doing this in public. She still does it when she wants a snack or something at home. But I just tell her NO and keep to my word, and after about 10 minutes she gets the picture.
Different ways work with different kids and parents.
Just be careful that the child doesn't harm themselves. Sometimes they don't realize how angry they really can get. Just stay calm, and it will eventually stop. If you say NO, stick to it. Don't give in, it makes things worst when you always change your mind.