That type of ending is not unheard of. Just look at the following shows:
St. Elsewhere – The imaginings of an autistic boy’s mind
Newhart – Bob Newhart wakes up in bed with Suzanne Plushette (his old tv wife from The Bob Newhart Show) and his live as a Vermont Innkeeper was all a dream.
Rosanne – At the end we find out Dan really died, and all kinds of things are different than what we thought as she’s writing her memoirs
So this type of ending isn’t unusual, but often unsatisfying to the viewer. Would Adam and Eddy, though, actually end their show in this manner? I think not but it would be an interesting twist just to see the fandom implode. A zillion points if Emma, Neal and Henry end up together in the end. I might even throw in Regina as Henry’s adopted mom. 😉
Keeper of Rumplestiltskin's and Neal's spears and war paint and crystal ball.