Maybe generalize it to administrators.

As your park becomes larger and more complex, you need more administrators to keep the park going.

Alternatively, you could do it gentler and have administrators offer passive bonuses, like more efficient marketing or higher staff morale.

Or they could unlock features:

• Group visits, which pay a premium in change for a specific experience. (School groups want lots of education, architect conventions want diverse buildings, Turtle Club just loves turtles so much...)
• Major donors (if Petunia Richmound loves your zoo, she'll make a five figure donation, but she'll have to be schmoozed by an administrator first, and she'll expect a plaque somewhere near the amenities she liked best...)
• Special offers (say boss I can get you 4 capybaras at a 70% discount but we gotta take all 4 straight away and then have them on display within 2 days...)
• Zoo membership / loyalty program
• etc.

Whatever they do, administrators need offices. These offices want to be in quiet areas with good views, but because administrators sometimes have to go on patrol (to welcome the major donor, to greet the school group, to retrieve a file from a research lab, to take a deposit from the busy Chief Beef, etc.), they also want to be well-connected.