I think many online exchange site have getting that kind of information from people using there site and sometimes you need to present something for confirmation before doing anything, I highly recommend to just follow the rules or term of using the exchange site.
This is what bittrex does today. Bittrex implements a verification process that makes some people upset and there is also a welcome with a positive. some people say that they are late withdrawing because they have to first process the data done and this certainly makes them lose. personally, bittrex parties should make announcements in advance or conduct experiments when applying this regulation, with the option of coming weeks to enforce this regulation in full. yes maybe now there are some people who leave bittrex, we all know that at this time very many exchanges are popping up and they the majority offer a very interesting. we'll see whether bittrex as the best exchange at this time can maintain the number of users or not.
Technically speaking, this is a good move on the part of Bittrex. I mean requiring identification only further legitimizes their business. I think it is sort of shady how they did not pre-inform their userbase, but in reality it does not make sense for them to do that at all seeing as most would simply withdraw their Bitcoin(s) before the new security feature was even implemented and they lose half teir business or whatever overnight. This way, most of their customers will not go through the hassle of verification and rather will stay with them. Again, it is kind of shady, but also makes sense.