It's just a rivalry for Scottish people against a neighbouring country, for the vast majority of people it's nothing whatsoever to do with jealousy or hatred (although I am somewhat jealous of any country who's at the world cup, be it England or North Korea).
Scotland are awful, and we'll be lucky to qualify again for a major tournament for a long time unless there's an influx of young talent sometime soon. On the plus side, at least we realize we're not a good team and hold no delusions that we'll win the world cup