Hong Kong is just a microcosm of China if you look a little deeper. They have some of the best of the best Chinese but they also have the worst of the worst. And I am betting the latter is just a small minority, hopefully. Please do not generalize and condemn all Hongkongers.
Almost 20 years ago in Hong Kong, I sat with my mom in a restaurant for lunch. My mom who was at that time in her 80's and had already shown signs of Alzheimer, accidentally butted her chair against a woman sitting at the next table. This woman came back with her wrath with the 5 minutes of cursing towards my mom. I had to restrain myself from starting a fight.
I am saying all this as a reminder to all our fellow Chinese, do not let an instance or two decide that Hongkongers are anti-mainland Chinese. Those bad apples are just bad and it so happens mainland Chinese visitors are becoming easy targets nowadays.
(Written in English because it would take me 2 hours to type in Chinese with pinyin. I am still learning.)