I have a strong feeling this is because the US government is pressuring every group/company that's working with crypto. It wouldn't surprise me if Bittrex was approached, shown BTC-e, and highly suggested they begin to limit actions of unverified users if they want to keep operating. I'm in the US and it's quite frustrating how antagonistic my government is to crypto.
amongst the borderline retarded replies in this thread (for some reason) - I would like to strongly emphasize and re-iterate the sentiment of this comment. To be abundantly clear, I think this individual has it EXACTLY correct.