Clouds, of course, are not unique to Japan. But clouds (kumo in Japanese) have special significance in Japanese culture, which makes them interesting subjects for hashioki.
Clouds that look a lot like these two examples often appear in Buddhist art as the heavenly platform for buddhas and bodhisattvas. The nice thing about clouds is that they allow a Buddha figure to hover above or float to earth while remaining fully upright.
These are also the kind of clouds that lighting bolts and dragons emerge from, at least in Japanese art.
This blue and white cloud is a chopstick rest from the Italian design firm of Alessi. (Another Alessi hashioki is featured in my post “Gotta love this fish” from August 2016.) It reminds me of the clouds that sometimes obscure the transition between different scenes on a Japanese folding screen (byobu) or scroll, especially when that art work has a “bird’s eye perspective” which invites the viewer to look down on a house or garden from above.
But chances are that when someone sets a table with cloud hashioki they’re not thinking about any of these things; they’re just thinking about the pretty puffy things that float across the sky.