the emac doesn't have a handle because its fifty friggin pounds, and should not be lifted with one arm, but cradled in both.
the iBook doesn't have a handle now because people razzed the hello kitty purse/toilet seat clam shell design (which I still prefer ergonomically, but doesn't stack with a set of books as well)
The g4 is a different case (no pun intended). Those handles are useful. That french mock up has nothing to grab the thing by to move it unless you tipped it over into your arms.
the iBook doesn't have a handle now because people razzed the hello kitty purse/toilet seat clam shell design (which I still prefer ergonomically, but doesn't stack with a set of books as well)
The g4 is a different case (no pun intended). Those handles are useful. That french mock up has nothing to grab the thing by to move it unless you tipped it over into your arms.