4 seat cars can be good for a driver who want a small lightweight gas saving car with enough seats to carry 3 passengers, animals like dogs, and bigger items like boxes, wood, which do not fit in the trunk. Having 4 seats instead of 5 seat will make a car use less gas because the car can be less wide, so the car does not need to use as much metal, plastic, and seating material to make a wider car and back car seat to comfortably fit 3 average size people in the back seat. Having only two passengers in the back instead of three will also make a car use less gas.Having a car with 4 seats can be useful if the car owner mainly use the back seat for carrying things like boxes, and groceries which don't need seatbelts.
But, I feel cars with 4 seats are not a good for people who need 5 or more car seats. Buyers usually are not saving a lot of money by buying a 4 seat car because there are already many cheap new and used 5 seat cars. The extra weight of a 5 seat car vs a 4 seat car may not save a lot of gas where the gas savings is very noticeable.
There are also smaller 4 seat vehicles similar to 4 wheel motorbikes.
I think small 4 seat vehicles may reduce traffic as well since people can use one car to carry 4 people instead of 4 individual people needing to each drive a 1 seater car , motor bike, bicycle, walk or 2 people needing to use a 2 seater car.
You can also carry more big things like boxes, food, and household supplies like soap and paper towels in a 4 seat car, so you don't have to take as many trips from your home to a store to buy the same amount of things. A 1 to 2 seat car may not have as much carrying space for carrying more things, so you need to be on the road more to go back and forth between locations to carry the same amount of things and people as a car with a back seat which can be used for carrying things.
I feel a car with 5 seats would usually have more space for carrying 5 passengers and stuff. But, there maybe some luxury cars which only have four seats because the center part of the back seat is used for an armrest with cup holders.
A 5 seat car can be a better choice for most families and people who carry many people in their car, but don't want to drive a van, SUV, or truck which sometimes can carry 5 and more passengers.
A 5 seat car can be a better choice for a car you plan to use for a taxi or online taxi service like Uber or Lyft since some people share one taxi ride with 4 friends or family members to save money and time.
