70% of Iceland's exports are from fishing and the EU's draconian and shambolic CFP would decimate Iceland's economy. Forget about the Icelandic banks going bust, they're small fry compared to the fishing industry and you can't eat krónur.
The CFP imposes strict quotas on the amount of fish a fisherman can catch with swingeing fines for catching over their quota. Such is the inflexibility of the CFP (it doesn't allow a fisherman to go over quota one month and then under the next to average their catch out) that a million tons of fish a year are thrown overboard dead to avoid paying the fines. And this policy was supposedly brought in to help conserve fish stocks!
The EU is "negotiating" with Iceland over the CFP which will be a careful balancing act ensuring no material changes are made to what is on offer whilst spinning superficial, temporary concessions as agreeing to Iceland's "red lines". The Icelandic government is sold on the idea of EU membership because it has no idea how to get the country out of recession but the ultimate decision lies with the Icelandic people who will have to agree to EU membership. They'd be insane to join the EU but as we all know, the EU doesn't take no for an answer and they'll just keep on asking again and again until they get the "right" answer.