| Value | ★★☆ | Effort | ★★☆ |
Give your customers a chance to experience your wonderful services together. Leave your branded anchor in their memory.
In the modern world of a widespread atomization, people are longing for group activities. Why not use it for a mutual benefit between customers and companies.

The reason for 2/3 Effort rating for me is that setting the process across the landscape requires a little more than just adding more customer records onto appointments in Salesforce.
Source: Invite Customers to Enroll in Group Service Appointments