You don't need to touch them to see if they are on. Listen for the cycle on/off. It's kind of a click.
If you do "test" them, it takes some of the charge down. They don't use that much electricity unless they deliver a shock. The deep cycle batteries can last a long time, but they do run low sometimes before the rangers can bring replacements.
A few years ago at Half Moon I accidentally touched a wire when it was live. I thought to myself, and said to our group, "If I were a bear, that wouldn't slow me down." Next morning someone asked if I knew what happened to our garbage, and did we put it in the fence. I said, "Yes, you carried it up and I followed you with a drybox." We found the place where the bear leaned in on the fence, bent it over, and reached in to the middle and grabbed our trash bag. One of our group tracked where the bear went upstream, then up a hill. We collected the scattered trash, and the other person commented that all the trash was very clean. Licked clean. I was bummed to be part of a group that helped train a bear that there's good stuff in those fences. I think that bear already knew it, though.
A year prior, someone told a story about "His friend Dave" who likes to make LOTS of bacon. They put the grease in a milk carton, let it harden, then put it in the garbage. The person telling the story was hauling the garbage, and apparently one day it was warm enough the grease didn't harden all the way, and a bunch spilled on one of his tubes. He reported that when he woke up that morning, one quarter of his raft was cleaner than he had ever seen it before....
The ranges are really encouraging folks to STOP leaving so many pumpkins. It really doesn't support LNT ethics, and it's gotten out of hand. And it might be feeding the bears!