I imagine the people most likely to do this would be farmers who are also into WAM. Lots of farm work is potentially or definitely mucky, even without any deliberate intention from the person doing it to get messy.
When I owned a farm, I had rough roads that led into the bush. Some of them had low spots that would become very muddy and I'd get stuck. When I had time (and energy) I would load rocks onto my trailer and drop them into the low muddy areas to 'pave' them so I could drive on them better. On several occasions, dropping heavy rocks onto the mud caused it to splash back at me. It would have been a great time to have a couple female farm hands helping me.
I haven't been messy on purpose for nearly a year due to having a break for health problems but on a studio day filming with models, mixing gunge and cleaning up by the end of it I look like I've been in the gunge tank myself. Also if I eat in a restaurant I have to get something with no sauce because you can guarantee I'll drop it. Nightmare clumsiness.
I don't really get messy outside WAM, I hate gardening so that excludes mud. Several years ago I used to like messing with old cars so that got a bit oily and I also used to help out at a heritage railway working on steam trains, but that was just Ash and soot, so not really WAM material