When they say “no vacuum cleaners,” pay attention.

Across the animal kingdom, there seems to be a general consensus that the hoover poses the greatest threat, for whatever reason. It’s difficult to pinpoint just why all animals perceive it as such a threat, yet that is what they do. They’ll do almost anything to avoid coming into contact with that monster. This also applies to these cats. To avoid the hoover, they climbed to the tallest point they could find.

9999 monkeys
Additionally, they are letting their owners know that they find the hoover to be an annoyance. To ward it off, they are baring their most menacing fangs.