An alarm clock's function is to wake you at a specific time. A snooze button's function is to delay that wakening. It's as rational as popping up an "Are You Sure?" dialog box.
For people who don't want to get out of bed as soon as the alarm goes off, but who also don't want to risk sleeping for another hour, a snooze button is perfectly sensible.
Yeah, but it would be nice to force myself to get out of bed each time the alarm goes off, immediately, and without fail. This is somewhat of a tangent, but I think that when I set a bunch of alarms on my phone (for 9:00, 9:30, 10:00, and 10:30, for example), it's actually harmful because I'm training myself to not wake up immediately. I stand up when the first alarm goes off and think "Man, I am super tired.. My legs are like jelly. Hey, I can sleep for a little while longer since more alarms are set." The result is that I'm usually late for whatever it is I have my alarms set for, since by the last alarm I've already trained myself to just jump back in bed. It's totally illogical.
I'm still 20, so maybe this behavior will diminish with age. But I'll probably try some experiments, like only having one alarm set (with snooze disabled).
It sounds a bit strange and it feels a bit strange too, but you can practice getting up when the alarm goes off.
Before you go to sleep, set an alarm like a minute in the future. Lay down, close your eyes, relax. Then, when the alarm goes off get up immediately, stretch a bit, etc.
Do this a couple of times (3, 5, 10 ;) and your brain will get used to the idea of getting up when the alarm goes off. Works like a charm for me (I tend to fall into the snooze-habit too)
I can offer anectdotal confirmation: I've never used my snooze button, and I can almost always get out of bed, immediately alert, as soon as my alarm goes off.
