In the case of your DPSS handhelds--
Peak pulse power is generally higher than CW power. Slightly more stored energy can make a monumental difference. DPSS wants the highest input power as possible-- which pulsed often supplies more. Though it's not entirely relevant for pen lasers as the pulse duration isn't short enough to supply a more constant peak.
Another good thing about pulsed is the duty cycle being longer. With these odd DPSS processes (and considering you purchased it as a POINTER) the duty cycle is very necessary. A way to extend that is pulsing the laser. (It is, after all, spending more time in the OFF state)
Though, I wouldn't say it grants longer battery life. Maybe very slightly, but nothing anybody would take notice to.