Most of the available seating would be far enough off the center axis that every time the plane banked you’d experience a rapid drop or acceleration as your wing fell or flipped up.

And then there is the paucity of usable window space.

Because the "cheap seats" further away from the centerline would be like a six hour roller coaster ride at Six Flags.

The centerline seats would have no windows (doesn't matter to me, but does for some people).

Barf Express.