At first I didn't consider that some of Greg's chips were catalin or plastic. Yet whatever they are, dealer button chips (lammers) are often
made to look different (and cheaper) than regular chips.

Anyway most of the world uses (or used to use) plastic (non-clay) gambling chips in and out of casinos. Pictured below are
plastic chips used in some major Cuban casinos long ago (pre-Castro). Some are catalin, and the others are an even cheaper plastic.
The orange Tropicana has 3.00 on the reverse. The green Copacabana has $20.00 on the reverse.

Robert