Yes, collecting sample chips is a popular niche in chip collecting. Over the years, there have been quite a few manufacturers and/or distributors of chips. Samples were/are a way of showing capabilities (colors, sizes, molds, security features, etc.) and as advertising to give to a prospective buyer -- casinos or home game purchasers.

They sell for a few dollars up to a few hundred dollars each, depending on age and desirability.

At one time, a few of the chip makers had retail stores, but not any longer. These days, the best sources are at the annual GGE Expo in Las Vegas, and similar trade shows, though it's getting tougher for someone without connections to get sample chips. Fortunately, a few club members have friendly connections and get some samples for sale at the club convention, on the internet, etc.

Look for samples on eBay. Also check the chip manufacturer / distributor websites, as some do sell samples to the public. For instance, Classic Poker Chips sells samples on their website (It's owned by 3 members of the club, FYI.) Their lineage traces back to the Burt Company, a pioneer in making chips and an interesting history -- see brief history on the CPC website.

GPI (Paulson, Bud Jones, B et G) don't sell to the public any longer, but you'll find them in the secondary market.

This just scratches the surface about chip makers and their samples ... an interesting area of collecting.