KYC when buying ICO tokens

[Julia_KA]

Hello guys! Would be very grateful if you could share your KYC experience when buying tokens on an ICO for cryptocurrency.
Some ICO's require going through KYC procedure where other don't, and sometimes they require going through the KYC only if fiat is involved. I personally only went through KYC when registered on cex.io exchange, but that service involves fiat and Naga tokens were sold for crypto w/o KYC.
Will be very grateful for your insights!   

[ARtema]

I wondering the same.
What worries me more is that in what cases I can be banned