Coins are just method of payment while tokens may present a companys share, give access to product or service and perform many other functions. Coins are currencies that can be used for buying and selling things. You can buy a token with a coin, but not vice versa. Coin operates independently, while token has a specific use in the projects ecosystem.
Creating a token is easier than creating a coin, as you dont have to create a new code or modify already existing one you just use a standard template from platforms like Ethereum, that are blockchain-based and allow anyone to create tokens in just few steps. Using a template for creating tokens provides smooth interoperability, so users can store different types of tokens in one wallet. Ethereum was the first to simplify the process of creating a token, being not the last reason why tokens flooded the market.