Around here I've seen tools on both types of bikes. I will say that I've seen more on sportbikes but that probably is because it's a younger average age on these bikes.
There are several higher end 'custom cruiser' tupe bikes about here with the bigger engines and it never fails when they see the wife and I on our sportbikes they love to show me what they have.
I used to own a BigDog Bulldog so I know about these bikes and like them but it's definitely not JUST the sportbike riders around here that like to show off.