Simon Jenkins thinks that airlines overbook because “careless passengers often fail to show up” (Our target-driven corporate culture is failing customers, 13 April). Tosh. Do theatres book seats twice because sometimes people don’t show up? Does London’s Festival Hall sell 110% of its tickets? Airlines rely on selling more seats than they really have, just as they rely on many other devices to wring more money from passengers, because their business model is wrong. Flying costs more than the customer is charged.

The “cheap” seat is misleading, and will become ever more so when airlines are forced to pay for the extraordinary damage they are doing to the environment, in terms of both air and noise pollution. Careless passengers? Oops, I forgot my flight from London to Malaga today. Maybe throwing away €150 or more is careless in Jenkins’s world, but in mine it’s not.

Paul Griseri

La Genetouze, France

• Simon Jenkins on the United saga tells us we have only ourselves to blame for shoddy service from big business. He overlooks the simple fact that airlines would not suffer a surfeit of passengers if they could resist the temptation to sell seats twice. This does not happen at the sports stadium, theatre, concert or restaurant – all of which manage to make a profit regardless. The airlines are greedy.

Andrew Lugton

Harrow, Middlesex

• In 2009, the Canadian musician Dave Carroll released a music video called “United Breaks Guitars” after the airline broke his valuable guitar. It has since garnered more than 15m hits on YouTube, and the episode became a PR disaster for United.

To its credit, the airline asked to use the video in customer-service training. It doesn’t seem to have learned a great deal since then. Time, perhaps, for Carroll to compose a follow-up – “United Breaks Your Face”?

Clifton Melvin

Chalfont St Giles, Buckinghamshire

• Shouldn’t someone have told United Airlines that the phrase “bumping passengers off an overbooked flight” wasn’t meant to be taken literally (Asia seethes over footage of passenger manhandled off US plane, 13 April)?

Fay Marshall

Brighton

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