This option enables you to tag a room to be booked by multiple people for the same time.
As each hospitality order relies on a room booking, to be able to accept multiple orders from different people for the same room and time, you need to allow those people to all book the room at the same time.
This is managed within your hospitality manager outlet, Hospitality, Room Setup
Set up the Boardroom as a Multiple Occupancy room using the tick box in the Setup page
User A books the boardroom on 1st June from 10am to 11am
This is marked on the room booking calendar as booked
User A places their order for this booking
User B also books the boardroom on 1st June from 9.30am to 11.30am
User C books it from 10am to 11.30am etc
All users are able to place their own order against their own room booking