Integrations are used for multiple reasons: order management, fulfillment, sending funnel orders to different platforms, and more.
One advantage of direct integration is sending funnel orders to Shopify, and fulfilling them there with 0% transaction fees.
You can also use integrations to manage your orders on platforms such as Google Sheets.
Lastly, you can integrate directly with an email sending platform (e.g. Active Campaign. Klaviyo, and Mailchimp) Once a funnel order has been placed, the email platform automatically sends your customer an email message.