The Truth About Airline Hubs, Bag Fees, and Open Seating

What do airline fleet and route decisions actually mean for your ticket price, your seat, and your bag? Here are the questions people really ask.

Why do airlines still use hub-and-spoke routes?

Because they make money. After US deregulation in 1978, full-service carriers like American, United, and Delta reorganized around hub-and-spoke networks—Delta centered on Atlanta. These networks exploit economies of density: more passengers per route lowers the cost per passenger (Elsevier). That's why you can fly from a small city to a huge hub and then onward to almost anywhere. It's not a conspiracy; it's math. But it also means delays cascade. A storm in Atlanta can wreck your connection from Omaha to Orlando.

Are low-cost carriers really cheaper?

Yes, but you get what you pay for. On continental routes, low-cost carriers can deliver roughly 80% of the service quality at less than 50% of the cost of network carriers (Elsevier). That cost gap comes from point-to-point networks—no complex hub banking. Southwest, Westjet, and Ryanair are the classic examples. But the trade-off is fewer frequencies, no lounges, and often no interline agreements. If your flight cancels, you're on your own more often than with a legacy carrier.

Do I still get free checked bags?

Mostly no. Southwest ended its 'bags fly free' policy for bookings made on or after 28 May 2025. Now it charges $35 for the first checked bag and $45 for the second, though Business Select and A-List Preferred passengers still get two free bags (CBS News). That's a big shift. US airlines collected about $7.27 billion in checked-bag fees in 2024, up from $7.07 billion in 2023 (CBS News). So the fees are real revenue, not a nudge to pack light. My advice: if you check bags, factor that $35–$70 round-trip into your fare comparison. A 'cheap' $99 fare can become $169 fast.

What's the difference between weight and piece concepts for baggage?

Airlines use either a weight concept (allowance by total weight) or a piece concept (allowance by number of bags with a per-bag weight limit). Emirates, for example, uses weight concept in most markets: Economy ranges from 20 kg to 35 kg depending on fare, Business is 40 kg, and First is 50 kg. On flights to/from the Americas, it switches to piece concept: Economy gets 2 pieces up to 23 kg each, Business/First 2 pieces up to 32 kg each (Emirates baggage). Under the weight concept, each checked bag can weigh up to 32 kg and total dimensions must not exceed 203 cm. This matters because a 23 kg bag on a weight-concept ticket might be fine, but on a piece-concept ticket it's the max per bag.

Is seat pitch the same as legroom?

Not exactly. Seat pitch is the distance between seats, measured from any point on a seat to the corresponding point on the seat in front or behind (Airlines for America glossary). It's a proxy for legroom, but seat design and thickness affect actual space. A 31-inch pitch on one airline can feel tighter than 31 inches on another. Always check the specific aircraft and seat map.

Did Southwest really get rid of open seating?

Yes. Southwest retired its open-seating system on 27 January 2026, introducing assigned seats in Standard, Preferred, and Extra Legroom categories (AP News). This is a huge change for a carrier that built its brand on cattle-call boarding. The upside: no more anxiety about checking in exactly 24 hours ahead. The downside: the cheapest 'Standard' seats are likely to be middle seats in the back. If you want a good seat, you'll pay up—or fly a different airline.

What about carry-on rules?

They're stricter than you think. Emirates carry-on allowances are 7 kg in Economy, 10 kg in Premium Economy, and 7 kg plus a 7 kg briefcase or garment bag in Business and First Class (Emirates carry-on baggage). Bags must fit within 55 x 38 x 22 cm. And liquids? The TSA 3-1-1 rule still applies: containers of 3.4 ounces (100 ml) or less in one quart-size bag (TSA liquids rule). Don't try to sneak a full-size shampoo—it will be confiscated.

Bottom line

Know the rules before you book. Check the baggage concept (weight vs. piece), the seat pitch, and whether your fare includes a checked bag. If you're flying Southwest, expect to pay for bags and choose your seat. If you're on a low-cost carrier, pack light and bring a carry-on that fits the 55 x 38 x 22 cm limit. The cheapest fare is rarely the best deal once fees pile on.

Sources

• Elsevier (airline economics) - https://www.sciencedirect.com/science/article/abs/pii/S0739885905130030
• CBS News (Southwest checked-bag fees) - https://www.cbsnews.com/news/southwest-airlines-new-checked-bag-fee-35/
• Emirates baggage - https://www.emirates.com/us/english/before-you-fly/baggage/checked-baggage/
• AP News (Southwest assigned seating) - https://apnews.com/article/southwest-airlines-assigned-seats-open-seating-ends-0f131c413349a14072f78288e5c056b2
• TSA liquids rule - https://www.tsa.gov/travel/frequently-asked-questions/liquids-aerosols-and-gels-rule