Most customers don't actually interact with CRM-y tools (usually). There might be integrations to (revenue cycle management for example) from customer facing to back-office, but that's usually the delineation.

But to your point, there's some grey area here.

I think you're confusing it with backend. Generally in traditional businesses you have reception/front desk where the customer interacts with the business and the back office where all the employees are doing various work.

Do you let the customers enter the back office in real life :-)