Would a ban on plastic bags just mean that I’ll have to use paper bags?
No. If you forget your reusable bag, and are making a small purchase, carry the purchase home. If you need a bag, ask for compostable. If your only options are paper or plastic, choose paper. If stores carry both paper and compostable plastic, then paper use will increase only if more customers ask for paper than they do now. In the early days of the ordinance, it is possible that grocery stores might encourage the use of paper bags, but as the compostable plastic bag market and production continues to expand worldwide the unit price will continue to drop well below that of paper and stores will certainly switch to using more compostable plastic. If customers are encouraged to bring re-usable bags, that would further reduce the number of paper AND compostable bags being used.