Is it illegal to drink beer in front of children?!

MY dad was watching a sports event with some men he knows from work. They were drinking beer. My little brother was there, my boyfriend who I was really angry at because he wasnt spending time with me and instead was watching that stupid baseball game, and sons of the other men. I told my dad that it was illegal and inappropriate to drink in front of children. He asked if I wanted to join them. I said NO! Than he asked me if I had any homework to do. I mentioned it to my mother and she said to let him alone and suggested that I and the daughter of one of the men find something else to do if we didnt want to watch the game. My dad should know better about what is legal because he works for a police department. Oh ya they had this high fat popcorn he made (lots of margarine), potatoe chips with mystery dip, and pizza. The pizza is ok I had some of that too. My boyfriend's mom keeps him on a strict low fat diet.