I suspect the problem was that your friend's hotel required him to login to the wifi network via a web page, which did not display correctly in Safari. Some Chinese websites are not friendly to non-IE browsers, either on Mac or Windows. Most of the time you'll be OK, but it doesn't completely surprise me that your friend had problems.

Of course, if your hotel has an open connection, you should be able to connect just like anywhere else, and there are also plenty of wifi hotspots in the major cities.