The common toilet was very different to the facilities we use today. Rather than a sensible attachment on the side for men, the male of the species was expected to urinate from a height of three feet into a bowl of water.

Add to the intrinsic accuracy problem the simple tenet that the male penis is squishy - well known for it in fact. So, essentially, the male was expected to part with fairly large volumes of liquid into a small area pumping it through a squishy hosepipe with an optional outer skin attachment at no extra charge.

After the would-be Robin Hood has had a chance to spread his bodily waste over a large area other patrons (Particularly Females) were expected to sit down on the previous mini waterfall site. Variations on this theme include particularly sadistic French toilets which were used in public areas. The doors of these would open in a time delay - ostensibly in case:-

1) The user was ill and needed help
2) The user was taking too much time of bodily functions, thus selfishly stealing the facilities from other would be patrons.
3) The user was busy with more carnal occupations - in which case everyone should be allowed to see.

Another type of French toilet involves squatting over a hole in the floor - a la 18th Century. Or the self flushing toilet floor. This has actually been used as a torture method on totally unrelated planets.
Another type of French toilet involves squatting over a hole in the floor - a la 18th Century. Or the self flushing toilet floor. This has actually been used as a torture method on totally unrelated planets.

There is really no need to wonder why 50% of the time humor was bathroom related.