Hope your week is off to a good start, @marblong.

We can definitely customize the option so the selection of a customer is not necessary.

My colleague, @ksiman is right.  If you are integrated, you'll need to call QuickBooks Time support if you no longer want customers in your account. They can uncheck that option in your QuickBooks preferences (it will be grayed out to you). This will prevent any more customers from coming over from your QuickBooks account and you can either have them unassign all team members from those customers or you can have them delete them. 

Here's how you can reach out to our awesome QuickBooks Time Support Team: Contact QuickBooks Time support.

If you aren't integrated you can unassign your employees from the customers or customize who is assigned to them. 

Any other questions you may have on this, I'm here to help. I'm only a post away! Have a fantatstic Monday.