why does the receiver get a copy of the form they completed

Hello,

Forms have email alerts included with them. There are also two types of email alerts:

1) Email Notification/Notifier - emails received by the form owner. He gets notified once he receives a submission

2) Email Autoresponder - emails received by the person who sent the form. This is usually associated to the email address field in the form. So if the form user (person who submitted the form) makes a submission, he gets informed that the submission was sent accordingly.

You can learn more about email alerts from this guide: https://www.jotform.com/help/30-Explanation-of-Email-Notification-and-Autoresponder-Settings 

If you have questions or if you need further clarification on this, please let us know. We'll be more than happy to assist.

Thanks.