This is a great idea, I already find these memos irritating (and not in the slightest bit tempting!) enough as it is.
Allowing me to set a limit and a bounce back refund is a nice balance I think. I think this is relatively 'low hanging fruit' in terms of implementing it, and I can't see there being too much disagreement.
Hopefully this will happen as I can only see myself getting more of them over time otherwise and it most certainly isn't desirable.