Well I'd argue what I'm suggesting is him being a LF with options. It wouldn't be the first time Maddon had a utility player starting daily at a different position(Zobrist). Either way, it's not a negative. All I'm saying is he's a left handed bat who might be able to play passable catcher. Let's say the cubs run out with 2 catchers who are righties normally. Schwarber gives you the option to do something different if your facing someone particularly tough on rightes even if it's only once a week.
And who knows, are we seriously doubting their scouting which seems to suggest that they think he is a C? By in large they've been rather spot on and the only reason any of us on this board are trying to move him away is because some other scouts have negative things to say about his defense. Ultimately I'm totally unconcerned. A bat like his appears to be you find a place in the lineup for. I may have thrown this out in this topic or some where else but Manny Ramirez was an absolute train wreck in LF defensively but his bat was good enough that they made due. So, as long as he is hitting who cares where he ends up? If we're talking about Vogelbach then fine it's a concern but even prior to the draft many viewed Schwarber as a LF/1B and some don't even view Vogelbach as a 1B. There's a clear distinction between the two. A lot of the people who didn't like Schwarber's defense prior to the draft have come out and said that he's better behind the plate than they expected(though it's obviously still not a sure thing).
Also, Schwarber has made comments to the effect that it pisses him off people don't think he can catch. Again, maybe he ultimately can't but he seems pretty determined to put the work in. And at the end of the day he doesn't have to be Yady Molina back there. If he ends up being a Castro level C his bat more than makes it a wash what you lose defensively. Piazza was arguably the worst C in the league defensively during his career and from 24-33 his worst season was 3.4 fWAR and he averaged 6.4 fWAR per season which is truly absurd when you consider 4 catchers last season were above 3 fWAR(Lucroy 6.2, Posey 5.6, Yan Gomes 4.6, and Salvador Perez 3.1). Schwarber probably wont be that good of a hitter but even if he's a minimal 3 fWAR per season he's a top 5 catcher. That's why it's worth totally exhausting every chance he can play at C.