Comment by selcuka

Text mode with user-definable multi-colour characters was mostly a 8-bit exclusive feature. Another reason C64 used that trick was the hardware scroll feature, which allowed shifting the whole screen between 0 to 7 pixels. It was much faster to copy 25x80 characters (as compared to copying a hires/multicolour bitmap with a 8 pixel offset) after the 7th pixel, and reset the scroll bit to 0.