Successfully completed tasks are paid out in stablecoins, DAI being a primary example, as backbone of the CryptoTask is AEternity blockchain with DAI having highest liquidity on AE.
CTask has a different utility and you may read about it at https://cryptotask.medium.com/ctask-token-utility-d4aac4ca69...
Good question. Nice to see that they prioritize stablecoins, it's what makes the most sense for general users. Anything that insists you use their utility token is showing you a red flag.