true .. some carbs overflow through a hole near the top outside of the bowl. But this gasoline spills out uncontrolled and gets all over everything .. (also, water and junk can get into this open hole)
my carb combines the two functions.
Overflow goes into the top of the open overflow-tube inside the bowl, and down into the drain and into the drain hose. The hose is routed away from the engine and exhaust.