We've come to like kaiten places (some more than others) when we are with our three-year-old. Yet, while I'm very laid-back about such things typically—butter on the counter for eternity, etc.—I always wonder how the heck they know how many times that piece of sushi has been around the belt, whether they pull items, and so on. The refrigeration while they circle is minimal.
At Sushiland the plates have a device attached on the bottom. There is a reader at one corner of the belt. [at Queen Anne it's at the back corner near the furthest booth. The sensor will indicate when a plate has reached it's time limit... Of course, they pile up plates off the belt to defeat the reader. That still doesn't stop me from eating there but there are some items that I'm not as inclined to eat unless I order them.
The last time I ate at Blue C Sushi at Alderwood Mall, a hippy guy sitting a couple of seats down from me kept putting his chopsticks directly into the wasabi container to then smear onto his sushi. I didn't confront him, but once he left I told the manager. She shrugged her shoulders and said it happens fairly often and then she took it away to supposedly empty and refill it. I haven't been back.
I'm very interested in this topic too. I've eaten at more than my fair share of kaiten places and have never once gotten sick. Is there some sort of refrigeration coming up from underneath the belts? I rarely (if ever) see any old food items being taken off the belt by the staff.
Or maybe the frequent consumers of kaiten fare will just build up more immunity for the eventual outbreak of the superflu. :-)