Coles has hoisted a white flag in the face of angry shoppers aggrieved by having to pay 15¢ for a "reusable" bag, and has promised to give them away for free until customers get used to bringing their own.

The supermarket chain's decision has raised the ire of environmental campaigners who say it is a return to the "bad old days" where plastic bags were used once and then discarded.

Coles and its rival Woolworths removed thin "single-use" plastic bags from their checkouts nationwide in July and late June, respectively, as a growing number of state governments ban the environmentally damaging items.

But offering only thicker, "reusable" plastic bags for 15¢ each has elicited howls of outrage from some quarters, and led to a series of backflips - including giving the reusable bags away for free for a short period of time while customers adapted to the changes - to quell the outcry.