This is why everyone needs to contact the American DOJ and complain about their actions against the publishers. If they aren't allowed to conspire to implement agency pricing then Amazon will gain a monopoly and force the authors to sign contracts just like this one. You have to understand that this is all part of the legacy publishing author development program. It's important that author's experience bad contracts like this so they know what to look out for in the future. Even if it costs more then the value of the contract it's important that you engage a lawyer and and an accountant to review the contract before you sign.
Oh sure you might think that the 70% that Amazon is offering looks pretty good but remember that's just the lobster and champaign dinner they're giving you before they take you back to their apartment and sign you up for a 3% contract. Amazon will do it out of pure corporate greed too, they won't have you best interest at heart.
I'm hoping to get a job working for the BPH perception management firms. I think with a little polishing around the rough edges I'll be in like Justin Bieber into a pack of 12 year old girls.