Indeed. Also very nearly always true with "fake" skeleton leaves used for crafting.

A small percentage (usually enlarged designs of particular shapes) are made with sophisticated latex presses, but most are chemically-stripped and treated real leaves (Ficus and suchlike) because it's simply easier to make them in bulk.

I was amazed by this at first — I bought some for a photography project simply assuming that their flexible, slightly springy nature meant they were artifically-made latex. But no: ficus leaves automatically processed in baking soda, essentially. The latex ones aren't even cheaper.