People in Japan are puzzled as Japanese felines have become immune to plastic cat-deterring spikes! The invention is used anywhere you wouldn't want the fur balls to step on - in the front yard, on top of the air conditioning units, along the tops of fences, etc. Also, the cat deterring spikes can be found indoors, protecting certain furniture or deterring the kitties from grabbing food off the table.
For years now, one could buy those cat-deterrent spikes (aka neko-yoke no togetoge in Japanese) at any 100-yen shop (think dollar stores). However, the golden days of the thingie are over, as recent pictures on the internet show the Japan supercats couldn't care less about the spikes - especially if there's a piece of tuna somewhere within the reach.
One of the theories is that due to prolonged exposure to the spikes the new generation of cats in Japan have mutated to adapt. I guess the cats are only laughing at a human attempt to stop them - and maybe even find their spiky "massage mats" therapeutic.