Could you quote the part of my post in which I suggest the cashier should 'berate customers for not bringing their own bags'?
Nowhere do I suggest anything of the sort. Here is my post again:
No, I still think that the default should be to assume that everyone nowadays takes their own bag.
Customers should have to actively ask for a bag, for lots of good reasons.
The cashier need say nothing. The onus is on the customer to ask for a bag.
I'm shocked at the way you have twisted my words to suit your own odd agenda.