Ah, I did not know that. We only earn SP from upvotes in the comment? Or you mean we earn no SBDs from upvoting (curation rewards)?
You want people to receive curation rewards in part in SBD? Hmmm... Can I inquire what's the motivation behind this idea?
Are you in the camp that auto-votes and bots are a problem that needs to be tackled?
You can read my post tomorrow and I'll explain it :)