Fortunately, with a category B licence, you can now hire an 8+1 passenger minibus, removing the four-wheeled barrier to larger family trips or other trips that require space. The rather large passenger compartment can be filled with more than just relatives.
There may be many occasions when a bus would be more efficient than a fleet of existing cars. The cost of petrol alone makes it worth considering hiring a temporary nine-seater. For example, family outings and gatherings, where instead of eight people following each other in two or three cars in formation to a destination, they can arrive together in a rented minibus, and the rental cost is much cheaper than the total cost of the fuel needed for the journey.
i.e.: Ford Transit