Why do you think you see cars with such tiny engines with so many exhaust pipes?people generally associate pops and bangs with a car being powerful and fast, so therefor want their car to be the same.
If you look closely you will see that the exhaust diameters on those are tiny. Or... like on the Ford ST they have a valve in the exhast that closes one to maintain exhust pressure when letting off on acceleration. I noticed this when following one the other day and it was actually quite distracting watching that thing flapping about like your grannies bingo wings. I'd rather have a single exhaust pipe than some kind of over engineered penis enlargement.