I agree that in scenes such as Times Square or Piccadilly Circus where there is a lot of advertisement real estate, this would be a more prominent solution, but

I agree that in scenes such as Times Square or Piccadilly Circus where there is a lot of advertisement real estate, this would be a more prominent solution, but for the vast majority of places (take for example a highway or some sort of country road?). A popup advertisement (I'm not in favor of them), as seen on YouTube or some Android Applications seem's more effective.