because the alternative is a metal cheaper than zinc, and that would pretty much be steel again, which didn't go to well in round 1 of steel cents. I suppose they could copper plate a steel cent core, it would bring the cost from something like $1.20 a pound for zinc to 40 cents or so a pound for steel. other than that, it would be doing a plastic or ceramic or some other material core and plate or galvanize or anodize that. but perceptions are funny, zinc already is a problem for people, they also weren't fond of steel cents but accepted it for the war. I guess copper plated steel could work to bring cost below a cent to make a cent, but it won't make people happy either. and non-metallic is pretty much out of the question I think, even plated.
