Board Game Arena

Why is it almost impossible to get an Arena game to fire? Is it basically just group of buddies arranging game times to play?

I presume you're referring to real-time games. For worker placement style games that take more than 30 mins to play, real-time time Arena games are very rare. Only the most popular games of this genre (e.g. Terra Mystica or Agricola) have a decent real-time Arena community.
If you want to play Carnegie in Arena you'll have to go turn-based.