I gave you reasons on why bitcoin gambling sites need licenses.

1. For your own security- We all know if you have a license, you always feel secured!
2. If you have a license means you doing all good and not illegal.
3. And last, based on softswiss.com. It is important to understand that a gambling license is absolutely necessary for an iGaming business to pass the application for a merchant bank account and to officially work with electronic payment systems. When the casino website is working with Bitcoin, all of payment processing can be performed internally with no third party services involved that can control the crypto payment infrastructure.