Why don't laptops use track instead of that pad?

A few years ago I spent $1200 on my first laptop and I totally hated the little rubber pad that you drag your finger across to move the mouse cursor. Why don't they make that into a trackball instead like on the Blackberry mobile phone? I took back my laptop and was hit with a $300 return charge, but I didn't care since the laptop was so slow even though the salesman claimed it was so fast with fancy specs. I noticed the newer laptops with Windows 7 seem to be faster, I may consider trying a laptop again if that is the case and buy one of those handheld USB trackball mice.