There are pictures of large pickup trucks (think Ford F250/F350) flattened like a pancake fire from trying to pass one of these without alerting the driver they're there. When you're on a mine, these things always have the right of way.
I could be mistaken but I believe they move materials in rock quarries, at least that's what I saw on an episode of some discovery show many years ago. I still think about them regularly too since it's like 3 stories tall and has a stair case to get to the driver seat lol