Why not have Blind Draft on Normals?

They've had a number of featured game modes that use Blind Draft (URF, Poro King, etc).

With Team Builder being the mode that lets you make the team you want, or get the lane you want, Why can't there be a Normal Blind Draft mode? (possibly replacing Blind pick, since TB is pretty much blind pick)

(Blind draft is each team bans 3 champs like in draft, after bans champ select is like Blind pick, where the enemy team cannot see your picks until loading screen.)