Eh, the click is there so they can measure it and get more transparency than a billboard. But even if you don't click on it, it's about as effective as a billboard - not useful for a specific sale but one more incremental bit of brand awareness.
That's wrong because it isn't the tiny banner ad that is the billboard, it's the website you get to when you click it. Budweiser doesn't sell beer on their home page, they advertise it.
