I have noticed this. It is like playing wack a mole trying to turn off my alarm on my wrist. Normally when the screen turns on with movement, it stays on for a LOT longer than when the alarm is going off. My arm moves to bring it up to see it, then the screen almost immediately shuts off.
I never snooze, but several times I've accidentally touched snooze, because the screen was off, and I was trying to get the screen back on. Then when getting ready for work (I put it on the charger) it all of a sudden goes off again (I thought I hit off, but hit snooze).
I think it isn't as refined a process as it could be... Well, 3 times of of 10 I have an issue, the other times I am quick enough to hit end before the screen shuts off.
If I actually charged my watch in my room I would actually be pissed about it. I get ready for work 2 hours before my wife, so if one of these snooze incidents happened, and I was out of the room, it would wake her up.