This page gives conflicting information. It implies you can't offer the product as if it were a "pre-order", and you can't even use "discount" as a reward, and mustn't imply the project page is a "store-front" for the product.
www.kickstarter.com/honest

Other crowdfunding platforms did allow people to "order the finished product" - and so I guess KS had to start allowing that too. However, depending on where people live, the project can then be subject to consumer protection laws. (i.e. It really is a store).

Looking here, it seems you are OK. When KS started, though, I thought the rules said that the end product couldn't be one of the rewards. That's because the funding was for the project process - which might not end in a viable product. i.e. "KS is not a store".
help.kickstarter.com/hc/en-us/art...

I see your "rewards" are actual copies of the book. I'm surprised that Kickstarter have allowed that. Maybe the rules have changed, and I don't understand it either.

OK -my take. Other "crowdfunding" platforms have different rules, and I think people have either forgotten the concept of KS (pledging gifts of money, to help get an arts project off the ground), or never knew it to start with, or are thoroughly confused by the differences.

And now looking remarkably #Solarpunk

You now have to settle the "Turnip vs. Swede" naming argument. We made lanterns out of swedes, in Manchester, in the 1960s.

www.youtube.com/watch?v=YL3A...

To be charitable, maybe it just means that most members and affiliates couldn’t really choose - as the candidates seemed too alike, and so either would as acceptable (or unacceptable) as the other. That closeness of result could have been generated by voters rolling dice.

www.youtube.com/watch?v=qae2...

Modern charabanc

Another fave...
www.youtube.com/watch?v=9mXl...