We have taxi which can take up to 5 passengers in Hong Kong. The following two photos are examples of fitting in five passengers in a taxi. The first one is usually when there is a big guy in the group, so the other four people need to squeeze at the back.
The second option is when there are two big guys in the group, so we would put two ladies at front. The 5 Seats taxis in Hong Kong are built for people to sit like this actually.
Toyota is not making any of these 5 Seats taxi anymore for Hong Kong market, so these taxis are going to fade out. The ratio between 5 Seats and 4 Seats are around half half now. Better grab four more friends and squeeze with you to experience that. Also remember to fasten your seatbelts.