Given your update, I would consider whether he has something keeping him from reading or isn't interested. I'm actually not a fan of delayed academics in general, as I know many here are, but I have seen one child who just resisted reading until about age 8. His parents eventually pulled him to homeschool so that he didn't have any pressure on him to learn to read. At 10, he reads on grade level.
How often do you work on the reading? How often can they exchange books? Being at #22 by this point in the year means he's only going through one book a week. Maybe he feels left behind if the other kids are far ahead of him. We are supposed to read a book every night. If other kids are doing that, then his resistance could be that every time you get the book out, he is reminded that he's behind.
Do you think he's actually pretending to miss things or reading slowly on purpose? (This is the second time this week I've posted this thought.) You don't say that he's demonstrating his reading elsewhere, so how do you know he's pretending? Maybe he isn't but feels your frustration (and I get it, I found it downright painful to listen to some of DS' early book reading attempts). I'm always careful not to tell my kids that I think they know something or should know it because I don't want them to feel badly if they *don't* know it.
As for rewards, I don't think that the occasional reward is harmful. After all, I work because I get paid. I often learn interesting facts while researching, but I don't want that to compensate me, rather than actual money. So, a child learns to read but also gets a sticker or piece of candy. As long as everything isn't tied to it, then I don't think it's a problem.