Because after ICO Tokens Can be buy anyone without submitting any KYC
Totally confusing this process

In my opinion, to increase security and reputation of a token, they require know-your-client kyc process to ensure that a person has no legal liabilities and also to avoid scams, because through kyc, the token maker knows who are their token holders and with that, they can easily track suspicious holders. And the identity usage is limited to that or else they might violate some laws. So there's nothing to worry about kyc process.