Travelling through a lot of airports in China I often see the "free wifi" stickers inviting you to connect. Upon connecting to the wifi, a gateway page asks you

Travelling through a lot of airports in China I often see the "free wifi" stickers inviting you to connect. Upon connecting to the wifi, a gateway page asks you to go the customer service counter where they take a copy of your passport before issuing you a user/pass for internet access. All I want to do is browse HN or blogs to pass the time but knowing they have tied my browsing to my passport makes me feel incredibly paranoid about it. If i go to the wrong blog, will they stop me at immigration on my next trip?