Why does Zendesk require the below permissions to authenticate with Google Apps?
Each permission is based on a feature that is needed to help manage your support addresses in a way where you don't have to leave Zendesk Support to do so.
Find below a breakdown of each permission and its corresponding reason for requesting access.
View your basic profile
Standard integration requirement to match your user name with your Zendesk credentials.
View and Manage the settings of a Google apps group
Streamlines the Google Apps groups with Zendesk groups sync to seamlessly update existing support addresses or add new ones.
Manage the email settings of users on your domain
Manages user creation when a new user emails this support address.
View and manage the provisioning of users on your domain
Manages agent user additions and removals and also helps with verification via Google Single Sign On.
View and manage the provisioning of groups on your domain
Allows you to provision new support addresses.
View and manage the provisioning of domains for your customers
Provides synchronization between your Support and Google accounts.
Manage your new site verifications with Google
Included for Help Center Google Analytics verifications, and SPF and DKIM record-setting.
For more information, see the article: Google Apps for Business - Mail redirection to Zendesk Support - Best Practices