They say typo. (Cynical me) says they got caught with their hand in the cookie jar. Part of me thinks they deliberately posted it at a higher cost, to gauge the reaction from the community. Needless to say, the feedback wasn't exactly positive. Then all of a sudden, they make a statement with "Oops sorry, we made a typo". Now, typo's are a possibility, but the fact that they made such a -specific- typo, makes me suspicious.
As I wrote on the STO forums, they would most likely sell more digital items, if they reduced the cost of the items. Instead (since F2P), they have continuously INCREASED the costs.