A few reasons for anything bigger: riding 2-up (Teresa got her fair share of it), accelerating uphills (it's hard to do with a 250 like Ciliegia, even in 2nd gear when it gets steep), or passing something there (like a lumber truck).
OK, they're not really city usage. But real world usage. And they have nothing to do with top speed at all.
Not that 250s are not good or anything
