it is because the word "token" means any item other than physical coins and paper money. for example those small "disks" that you see in casinos are also called "tokens" which act as currency within that casino space. so people sometimes refer to any cryptocurrency as "token" too.
and if you want to get too technical then ethereum is not a "coin" or a cryptocurrency' ethereum is a platform which itself has a token called "ether" or in its short form "ETH" that is used as the fuel for smart contracts.
The casino chips are considered tokens if they are only used to allow you to gain access to the casino's services, but if they become widely accepted as a medium of exchange (e.g. if you can buy bread using casino chips at any convenience store), then they have evolved into a currency.