If you have tap to wake turned on (it's on by default), you can tap the screen anywhere to wake it up. So long as the screen isn't already on and you don't mash the Snooze button, you should be able to hit stop.
I believe the power-button-to-snooze thing is meant as a usability boost for groggy people: the physical button may be easier to click than some random spot on the screen.
