Because he does.
http://www.comicbookresources.com/?p...ticle&id=58806
For me, if they have to have John Stewart on the Justice League right off the bat (and that would be a mistake, in my opinion)... then I really wouldn't mind it at all. I'm imagining the banter between Ben Affleck, Henry Cavill, Jason Momoa, and Tyrese, and I'd imagine it'd be pretty priceless.
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