They are pretty easy to chargeback as long as you initiate it within 30 days of your first transfer. Give a notarized letter to your bank stating that you did not do these ACH transfers to this "Coin Base" company.
You can get ACH charged back for up to 180 days with more involved procedure.
Terminate, yes. Report you to the police, not sure.
Chargebacks for small amounts are often paid by the bank itself because it's cheaper than actually disputing with the merchant, so banks will certainly terminate accounts of customers who abuse that.
You can get ACH charged back for up to 180 days with more involved procedure.