I tend to agree.
She COULD have tried the service desk first though, to see if they would turn her coins into dollars for a faster checkout. Save the cashier and people waiting in line behind her from the misery.
The store has their right to set their policies.
She wasn’t really doing anything wrong, just against the store policy.
I agree with you. There are ways around most things. It’s how you approach them that matters. Times I have opened my wallet and seen a $50 bill and a $5 bill when my purchase was less than $5. I always politely say “I do have a $5 but it would be really helpful if you could take the $50, however I understand if you can’t”. 9 times out of 10 they take it.
A preemptive request is usually very effective.
Yours is the most sensible idea. Set a limit of paying with coins at $5.00 at the register and ask anyone with more then that to go to the service desk.
BTW, you can also check out at the service desk.