Agreed. My little brother (18 years old) from the States has been out to visit us a few times and he stays a while each time. The time before last time he was here I needed to show immigration some paperwork regarding my salary and my immigration status to show that there were people who were legally in HK who could fully support him. I'm not sure what triggered the questions (it was his third visit, I think) but something did. Once we showed that he obviously was not working here or planning to overstay they had no problem with him. They didn't even ask questions the next time he visited.