poloniex beside US too, but they aren't act like Bittrex and scam their users. at least Bittrex should wearing their users and give them time to withdraw their funds. that is if Bittrex was a lighnt exchange.
https://news.bitcoin.com/cryptocurrency-exchange-poloniex-bought-circle/Poloniex will change too.
Bittrex is preparing to cater for the big big growth phase - the wallstreet traders. For that they have to have a higher standard of compliance and it will put them under further scrutiny.
I believe that exchanges that are of vague owneship or country of residence like HITbtc, Binance and Yobit may become increasingly a target for regulators.
In order to become a mainstream accepted exchange they have to comply with a variety of existing laws and increasing regulation.