Really depends on the pizza. Pan Crust pizza from Pizza Hut was my first pizza on which I thought the crust was absolutely worth eating.
Boboli crust is also pretty freakin' amazing, though when I make 'em I do spread a little sauce on the entire surface of the pizza.
In general, unless the pizza is horrible I'll eat the crust. But if it's good enough I'll eat it straight, without leaving sections of sauce-laden pizza to "cut" it with.