They're all over Indonesia, too! I spent 6 weeks by myself traveling in Bali and the other islands last summer. As usual, I carried my portable t.p. from WalMart. Squatting over that hole is tricky but flushing is even more difficult. In Indonesia, they have either buckets of water (overflowing from a nearby running spigot) or corner fountains of water (I thought they were for washing hands-ha ha). You scoop some of the water from the bucket or the fountain and pour it into the hole where, magically, it eventually disappears. In Indonesia, it disappears often into a river so don't go swimming! Naturally, from all this water overflowing and being splashed onto the tile floors, it is sloppy and slippery. There were several times I went in the bushes instead and I'm 64. If I can do it, you can!! P.S. I'd go back in a heartbeat.
Linda
San Diego