Absolutely!
It's inevitable that players are going to get hit with the ball every now and then (the goalies in particular). The defense has the option to do many things, one of which is have the defenders stand--at stick's length--between the goal and the player with the ball. Granted, offensive players don't want to purposely hit defensive players with the ball--as that could lead to a waste of possession--but they are certainly allowed to shoot as hard as they want with players standing in their way.