Which of the following is NOT a service typically offered by ultra low-cost carriers like Frontier?

Ultra low-cost carriers, such as Frontier, focus on providing the lowest base fares possible to attract price-sensitive travelers. This model usually entails minimizing costs wherever feasible, which translates into a range of services that are priced separately or not offered at all.

The reason why free in-flight meals are typically not part of this service model is tied to the ultra low-cost carrier's intention to keep base fares low. Instead of including complimentary meals, these airlines often charge for food and beverages available on board. This allows them to maintain low ticket prices while still offering optional services that passengers can choose to pay for if they desire.

In contrast, low fare tickets, optional add-on services (such as priority boarding or checked baggage), and tiered seating options are all common features of ultra low-cost carriers. They leverage these strategies to allow travelers the flexibility to customize their travel experience according to their needs and budget preferences.