You absolutely can withdraw without a payed miner, if you bought a miner at some point in time. This means that you can buy hashing power and sell off everything you have and pull out the BTC if you choose to go that path.
It is not explicitly stated anywhere, and sale fee is too damn high to try just to figure out that you may be not able to withdraw. I complained about this issue multiple times on this thread, first time several pages ago, and got no response from anybody affiliated with hashie. Instead, one moron wrote a shitload of stupid crap at my address. Where have you been, dude, you would save me so much typing? Thanks anyway.