Budget a cinema trip.
A cinema trip has three cost blocks that scale differently: tickets and concessions both multiply by party size, while travel and parking are fixed for the group. Separating them shows why a family outing costs so much more per head than the ticket price implies — concessions frequently account for a third or more of the total, and they are the only block you can cut without cutting the outing.
Trip total
Total = (ticket price + concessions per person) x party size + travel and parking
Concession share
Concession share = concessions total / trip total x 100
That is a judgement, but the surcharge multiplies by party size while the fixed travel cost does not, so a large group pays several times the premium a solo viewer does.
Usually discount days and matinee pricing, which often cut the ticket block by a third, followed by skipping the concession stand entirely.