It *could* cost consumers *if* prices are skewed towards certain rounding values according you America's central bank.
Meanwhile there have been studies in countries that have eliminated the lowest denomination coinage and this was found not to be the case in all of them. That is if you believe the central banks of Canada, Australia, New Zealand, Hungary, Belgium, Germany, Finland & The Netherlands. The main difference being these countries have already done it, and have actual data.
I remember seeing all the same prognostication before Canada made the change. It didn't come to fruition. I'll just agree to disagree. Have a good Saturday 🤙