A lot of custodial exchanges used to let you send/withdraw below a certain threshold without doing KYC. I don't know if they still do because I haven't used any custodial exchanges in a while. I was never forced to KYC on Bittrex but I never moved volume through there. I think Alby at least for now won't have to force anyone to KYC if the user's transaction volume value stays below $1000/month and $600 for any single transaction.