why's btc-e constantly lower than bitstamp? Harder to get money in? Easier to withdraw fiat? Less stringent KYC procedures?
Much more hassle to get USD in and out compared to other exchanges is my guess. You have to go through some weirdo third party services.
If getting fiat in and out is equally difficult, you wouldn't expect it to affect the price, would you? Unless the methods for withdrawing have benefits like anonymity.