I was fishing alone on a coastal holiday, about 2 miles from my car and beach was deserted and got a bout of the shits. I tried to hold it in as the fishing was too good to trek back, but it was real liquid stuff and the pressure was building. I checked for public, and then just stood with my back to the cliff, bent over slightly and let it go all over the limestone lol.
Luckily I always take hand towels for wiping off hands after unhooking etc, so I just gave a good old wipe with that fish stained badboy and carried on a fishin!