Checkbox Required?

Hello,

Love your plugin. Using the free version right now. I am using Contact Form 7 for the newsletter signup forms on my site. I have double opt-in checked off and was wondering do I need to use the checkbox [mc4wp_checkbox] on my forms for double opt in to work? If not required for double opt-in, is the checkbox a required field to add to the form for any reason? Meaning what purpose is it serving? Just trying to understand if I actually need it and why.

Thank you!

https://www.ads-software.com/plugins/mailchimp-for-wp/