Some physical coins contain private keys. In this case, the coin has value as a cryptocurrency until the private key is used and the address emptied of funds. You could even transfer more money to the coin, making it worth more or less than the cryptocurrency denomination that's printed on the coin.
The coins are typically made out of a metal, which has a value of its own. For example, Shibe Mint's silver dogecoin is made of 1 oz of silver, so it's worth at least ~$19.63. Since it's selling for $35, you could say that the "collectible" portion of the product is valued at ~$15. Even if it actually includes a private key for the 100 dogecoin it's denominated as, this doesn't significantly change this figure, since 100 dogecoin is about $0.06.