When you install ShipInsure, the default is set to opt-out. This means that if you have ShipInsure installed on your website and a customer goes to place an order, the widget will automatically be added to the order and they can unclick it if they don't want it.
If you don't feel comfortable with this, you can change it in our merchant page. There you can set it to opt-in, which means that for the customer to get our coverage they have to intentionally opt in by clicking the widget. You can change this setting either through your ShipInsure dashboard or through Shopify (click on apps, then click on ShipInsure, then click setting on the right and choose your desired setting).