Hey John,
This weekend in Los Angeles, we stopped by a Bristol Farms which used to be a favorite place to buy sushi-to-go. Like many stores do these days, they had a guy on the payroll who turns out sushi all day long. They still do, but it was a different guy this time, and I'd never go back for the sushi again. Other complaints aside, the rice in the rolls was thick and heavily pressed in a way that suggested to me that some evil-doer has invented a machine that extrudes the rice 'sheet'. Possibly, the machine even allows you to lay the ingredients in a trough of sorts and then it presses the rice around them. The result yields a product that is probably an 'improvement' from the restaurant store/labor point of view, both fast and uniform, but it's totally at the expense of the light, deft touch of hand-made. In what we experienced, the rice layer was so dense it was tough, and the fillings were a bit loose in a baggy nori sheet so they tended to drop out when you picked up a piece of roll. Each roll weighed about twice what you'd expect.
Am I onto something?