soo, the joke is that "hurrr my city is better than your city"?
Lise was pretty much parodying the "tension" that comes up every time it is "Norway vs Sweden" on even the slightest scale.
When reflecting on it, I have realized that this one was probably meant to be a joke understood by Norwegians mostly.
There is this feeling of "competition" between Norway and Sweden constantly amongst the people for some odd reason.
Well, we were all fed Swedish jokes since we were 3 years old and for some reason we still are angry that Sweden didn't help Norway during WW2 even when Germany was losing.
Also there is that whole thing with having been given to Sweden as a spoil of war after the Napoleonic war.
Amongst other things
There is a similar feeling with Denmark but more so with Sweden since our history with them is more recent.
I guess Norway is still an immature nation to some degree