In an article I am reading from Bloomberg Businessweek, there is a use of "staffs". I thought staff is a collective noun and has no plural. The full sentence reads
Companies such as Uber Technologies Inc. and DoorDash Inc. have established or expanded programs allowing employers to distribute meal credits to their staffs."
Shall I interpret "staffs" as different groups of staffers, just like "foods" mean different types of food, and in this context meaning one staff (group of employees) for each of the aforementioned employers (Uber, DoorDash)?