The kiosks at all the grocery stores where I've used them have offered the option of entering item codes, so it's a fair bet yours do too; if so, give it a try, and see if it doesn't save you considerable time.
Over there fresh fruits/vegs/bakery don't have any stickers/packaging/etc. You pick them, put in a bag and cashier rings them up along with barcoded items. They got a fatass book with pictures for newbies/self checkout and all experienced staff have muscle memory...
I still remember when I encountered this workflow for the first time. I didn't speak local language, cashier didn't speak english and I had no clue why cashier is so banana while ringing up my bananas :(
Around the university, the supermarket drew primarily from the adjacent neighborhoods, and got a lot of college students and local residents who were shopping on average weekly, so we quickly got skilled at using the machines. In the residential suburb, the supermarket draws from a much larger area, and there are more customers who shop there infrequently, so they never get skilled at using the machines. Even just as a skilled user, not as a professional checker, I would regularly stand in line behind people where I knew that I could have shaved minutes off their time merely if I had checked them out.
A lot of the skill involved was just in general operation: how to find barcodes, how to scan items reliably, how to identify produce and enter it correctly, how to use coupons, how to flag down help if the machine entered an unexpected state or required human assistance, how to use the payment terminal with cash, credit, and debit, how to bag items correctly and so that the machine would recognize them, what the various prompts mean and how to respond to them. There's a lot of complexity in operations which we denigrate as "unskilled" or "menial labor" which is only evident when you take the time to observe closely and see what people are actually doing in them.