Although the caption to the picture does not tell me how this cat ended up covered in polystyrene balls, I will speculate and say that it is due to static electricity on the cat’s coat. Also, the caption does not tell me that these are polystyrene balls but they very much look like it. These are very lightweight plastic particles which can be attracted by static electricity.
Some pages on cat welfare:
Static electricity is built up on a surface when materials are rubbed together which causes electrons to be transferred from one surface to the other. This in turn leaves one surface with in excess of positive charges (protons) and the other an excess of negative charges (electrons). It is more likely to happen in cold dry climates both inside and outside the home. This is likely to happen in winter on a dry, clear day.
The buildup of static electricity on domestic cat is an interesting subject which should not be ignored as it can result in an electric shock. It is possible I would have thought for a person to give their cat an electric shock through static electricity. For instance, if that person is wearing a polyester dressing gown and they take it off quickly and hang it up. And then reached down to stroke their cat it is quite feasible for electrons on their skin to be transmitted to their cat resulting in a mild electric shock.
If you would like to read a bit more about this subject you can click here. There is another issue regarding static and that is static electricity on the water bowl which might cause a cat to howl. Cats sometimes hiss for the same reason.
Finally, I would expect the picture on this page to have been set up and if not it would have to have been a series of unfortunate coincidences for this to happen. The cat would have to carry a static electricity charge and there would have to be polystyrene balls on the floor and finally the cat would have to roll in those particles, I suspect. Let’s say it would have been a rare coincidence for this to happen which is why I think this picture was set up.