It's good to see that the tradition of people in horror films making bad choices goes back to at least 1906. Here the characters decide to stay in a haunted house overnight, eating dinner, and even trying to sleep as though they are in a regular inn. What is very odd is that the main characters are made up to look like clowns in a circus with false noses and makeup rather than just normal people.
Melies had been making films with these kinds of "tricks" in them for some time, but this was an early attempt to use these tricks to tell a story versus just demonstrating the odd effects.
What is particularly well seen in this film is that humans, although immersed in a non-human universe, continue to behave quite normally as humans, as if nothing had happened, that is to say say notwithstanding the horror.
A great lesson that horror cinema will take hold of is that there are only two ways for cinema heroes to fight against terror: either to become terrible themselves or to take refuge in everyday gestures. But horror cinema can only lay claim to humor by adopting this second path; the human must be surprised in his derisory daily existence for the terror to reach the laughable.