Can you be more specific? They actually said they had everything made and printed, can't be that hard... they simply didn't end up having enough money for shipping costs because they went bankrupt for other reasons. Again, they made an accounting mistake, instead of earmarking the funds for shipping, they expected once the game launched they'd sell easily (they were greenlit in days, featured at the E3 etc), they'd easily manage shipping.
I mean let's be clear here, they had a bunch of artwork laying around already (we know this), artwork that ended up in a wallpaper, and they had rewards of $30 - $50 for the game + some digital stuff (e.g. an mp3 of the soundtrack) + getting this artwork mailed to them. Oh and the game was just $10.
So in effect they have a PDF on their computer, and they're charging $20 print and send it to you. (this isn't even the booklet, just the wallpaper, the booklet+wallpaper costs $40 extra ontop of the game).
Now you find me a scrappy indie game dev that doesn't want that, or can't handle it, or can't make that profitable. Don't act like that is rocket science. You telling me if you're running a small shop of 5 people and you're so scrappy you'll risk bankruptcy 6 months later, that printing and shipping a PDF for $20 to 1000 people isn't workable? That generating this $20k revenue (1/3rd of what they pulled in) from a wallpaper, can't be done for less than $10k everything included (printing, labor, shipping).
I mean hell I can print 1.000 A3s for less than $1k without much effort, already found a quote for that, and it'd be printed within a day. Again, they said they had everything printed and ready, that's not the issue here. Then I reward myself $3k for an entire month of effort of shipping pieces of paper (big deal, could do it in a week), and I spend $3 to mail 1 piece of paper each. I still make $13k, enough to pay a developer in Belgium for 3 months. And considering I spent $3k on the labor, I might as well outsource it to some highschool intern who gets a ridiculously royal salary of $3k for barely a week's worth of work. And I'm being pretty generous with the margins here, even if you nitpick here and there, and add some other factors, it's still a good deal. In fact I doubt they regretted their decision, merchandise was half their campaign revenue.
Now I KNOW there are companies that offer ridiculous stuff. 1) offer things they haven't made yet (like a mini comic to go along with the game, which requires a lot of time spent) and 2) things that make no economic sense (a $20 reward for a 3d printed game thingy, which costs $15 to make and $10 to ship, and time spent). And that this makes no economic sense and often fails.
My point is that while merchandise isn't always a good idea, it definitely can be, and that it probably was for this company.
As for a 'book order', it's just a booklet made out of a bit of paper, at a quantity of 1000 of them they cost about $1 each or so. Remember they're part of a $40 reward which has a booklet, wallpaper (combined <$2) and digital rewards like a soundtrack. Hardly unfeasible, this is on top of the $10 of the game's price.