After a few minutes search, I found self-checkout cashier are found at WALMART, etc. in the US as well but what's so amazing about RELUCK is how they trust their customers:

1. the place have such wide and open exit (no doors) without anyone checking what's within the customers' bag

2. the self-check out cashier is so close to the exit

3. unlike the self-checkout cashier at WALMART, there is no machine checking the weight of your groceries as mentioned in this blog post

The system is totally trust base.

Of course, this is only possible because the store is located within Gate-city Osaki, a building complex where such well-known corporation as Sony and Adobe reside; most of the people found there are the employees of such big companies and they wouldn't risk the chance of becoming criminals.

Another cool thing with RELUCK's self-checkout cashier is that you would pay them using the Japan's famous Osaifu-keitai (i.e.  RFID application for e-wallet built into most Japanese mobile phones).

If you choose to go self-checout at RELUCK, you would...

1. place your phone on  the card reader

2. scan the barcodes of every grocery you are buying 

3. check the total price and press "OK"

that's it.

It is one of the places you should check out, if you have an osaifu keitai and a chance to visit Osaki.