Why does Mr. or want the curse to end?

I think because the curse bounds everyone to Storybrooke so they can't leave town (with the exception 3 people). Bae isn't in Storybrooke so Mr. or needs to be able to leave town, I assume breaking it would then allow him to do so.

Which might mean the people of Storybrooke will have the option to return accueil to Fairytale Land ou stay in the real world. Not sure.

I'm pretty sure it has to do with Bae, whatever it is.