Connecting Grounded Thermal Pads and Ground Pins

If you have an IC with a grounded thermal pad, is it bad form to connect the GND pins to the pad to ground them? Or is there a reason to pull them out and ground them through vias? Thanks very much!

Usually the thermal pad is not connected or is connected to gnd. (electricly ) Ether way connect to ground. The ground pins need to go to ground, the board ground.