Birchbox.com

I bought my sisters each a birchbox 6-month subscription this past Christmas. I received an email from them on Feb */2016 saying they are cancelling and refunding it starting March 2016bon because of the "exchange rate and high shipping costs" they said. I am disgusted as number one I bought these as gifts and mostly because I look at my confirmed purchase as a contract between customer and business and just because the exchange rate has changed or shipping rates have changed they just decide to bow out everything. If I had decided 2 months in to the subscriptions that I wanted my money back...that would NOT have been an option. What makes them think this is at all acceptable? Here is a copy of my email...