Can I wake up my husband to go get me a drink and some snacks?
Why can you not get them yourself?
I don't want him sleeping longer than me.
As long as he has no obligations to meet, you should not wake him up beforehand. You can get a drink and snacks on your own if he is still asleep.
I wouldn't do it if he had work, but he doesn't work today.
It is still rude to wake him up while he is sleeping. If he doesn't have work then you can sleep in instead. You should be more respectful of your husband.