If you're going to be in Zion for only a day, I suggest you ride the shuttle and enjoy the beauty of the canyon, getting out at various stops for short hikes. As far as accommodations and food options, I own a seasonal home above the Park and sleep in my own bed. I believe there are reasonable...
I've been roaming Nevada rock hounding and hunting for over 35 years and have encountered snakes less than a dozen times. The closer you get to water, the more likely you may come across one.
Scorpions at night are another story. I buy a can of wasp and hornet killer. I hit the bottom of each...