Many Japanese restaurants serve one type of food in a few variations. Tonkatsu, Soba, Sushi, Donburi etc They have developed a system of varied dishes that suit the courses on offer and these are usually stacked in colourful shelves behind the counter.
Dishes for sauce, rice, sake, soup etc
The pestle is birch wood and grooves make crushing easier
Some restaurants have a signature style. This bowl is for us to crush the seeds to add to the rice rather than serving it on the rice.