Group travel can be tricky. You have a big number of people you have to get from point A to point B, and it can sometimes get expensive. If you are booking group travel, you will need to call the airline directly if you are booking 9 or more passengers on the same itinerary. Otherwise, you might end up paying more.
Airlines group their seating in categories. If there are 4 seats left in category A for $200 and 10 seats in category B for $250, you could end up paying different amounts and the price could continue to climb depending on how many seats are available. This is why the passenger’s number field only goes up to 8 passengers. For this exact reason, working with the airline directly ensures your entire group will be charged the same cost per seat. Groups usually require a deposit and the airlines do charge additional fees.