No Smoking Sign

I don't like smoking and i hate it more when people smoke inside a non-smoking area.

Today, i went to a restaurant to celebrate my birthday with my parents and also my grand mother and my girlfriend. We picked the non-smoking area and i think i have seen the no smoking sign at the restaurant today, but there was one guy who just smoked inside the non-smoking room. What makes me even more angry was that the waitress didn't told him to quit smoking inside the room