I'm just guessing, but when you create a post, you can set it for 100% power up, split it 50/50 between SBD and SD or not receive anything at all....I think it may have something to do with that and I'm assuming when you see the amount crossed out, it's the amount you COULD have made had you not selected no rewards.

As I said though, I'm guessing, but I think I'm at least in the right area lol