Late to the thread, but I can't help myself ... It's to show you, that you aren't fully in control of HDB and regardless of how you play him, it's (likely) still a man with a personality different from yours and with a certain past you can't change. Yes, it could be done a less embarassing way, but the message had to be powerful.
My favorite semi-racist moment was at the bottom of the Doomed Commercial Building where you got the option to paint your face black with coal to "ward evil spirits".