email address still required after unchecked to not be required

Due to the very specific need of our client, we got the request to not require the email address upon registration as some are older people without email address but register on friend's computer or family members. This is only needed to know who will be present. The ones that add email address then would be updated with the reminder. After removing the check mark to make not required, still requires the email address.
Is this correct or there is another location to remove this requirement?
Thanks!

Hello Joao

email and first_name are two required fields for every event and could not be optional. The system needs email field to send confirmation email to registrant when they register for the event

If you really want the field to be optional, you can submit a support ticket sending us super admin account of your site so that we can help editing the code to make it optional

Tuan