I emailed Red Box and here is their response:
Thank you for your email. I am very sorry that you have received this unexpected charge and I will be more than happy to explain things for you today.
Redbox often tests prices in order to understand the impact of price on our business. The updated price in your market is part of a localized test. At this time, no plans have been made to expand the test or to change pricing permanently.
I am in Utah and wonder what other markets get this "test"??? I bet price increases will be happening sooner than later for everyone.