Hello,
This is really solid premise and I absolutely love any kind of simulator type games anyway. The music is nice and I can vibe with for a long time. I really enjoyed the fake discount label things. I failed the first time because I kept trying to scan the barcode with the qrcode scanner because I didn't know there was a difference. In hindsight it's pretty obvious.
I also like that you made sure no one could start the game without clicking on 'how to play' so that's nice.
I absolutely am going to get carpal tunnel from having to use those scanners. I don't know if that's how they are supposed to work. But whenever I would pick up those scanners with right click, they would just keep spinning in circles which meant I had to hold the button for longer. I can see what you were going for but I felt that one was a unfair.
Good luck!