I used to live in a flat with a non contact toilet. There was no flush, just a bucket that you filled with water and poured in from a height. It doubled as the shower room so was a wet room. With regards to the hole, in my family toddlers tended to fall into them, or put things down them. Flip flops and remote controls were quite popular. One benefit was that it was very easy to empty the mop bucket. Nowadays, if you don't have access to an outside drain, it's very difficult for your maid to empty the mop bucket...