The banks want $100 bills eliminated (and recalled) too. They want savings of cash eliminated and the money put in banks where they can impose a negative interest.
They won't call it 'negative interest', but 'transaction fees' or some such. "Negative Interest" would cause riots and runs on the bank.
Negative interest does not make sense from a business perspective, unless I want to drain a bank of every last piece of hard currency when people pull out. I would think that to a large segment of depositors, I can find a variety of ways to keep my cash safe and more readily available if *earning* interest is no longer available as an incentive.
And if we have any reason to believe “negative interest” on deposit accounts will become common, now might be a good time to start converting some cash into precious metals.