Gary Wills, thanks. Now I see where you are coming from. 
If Jesus is truly present, body, blood, soul and divinity in the Eucharist, He is present whether we consume Him or not. Of course we must receive it, consume Him, but, just being in His presence imparts grace as well. Like Mary sitting at the feet of Jesus, etc. God can impart grace in many ways. 
And, if He is fully present, really and truly in the Eucharist, then we must worship Him in the Eucharistic species.