I think selling fully reusable cloth bags would be the right thing to do, but otherwise I agree that stores shouldn't offer single-use plastic bags any more.
But those complaints came in the first few weeks after the ban, and they dried up soon enough. Everyone learns eventually that they need to take their bags with them - at least I hope nobody is sitting at home now, five years after the ban, with 1000 reusable cloth bags.
P.S. I've found jute bags the best value for money. They seem to really last forever whereas the thin cloth type start wearing out after a while.