"Low-fare airlines cannot afford any frills"

So said the CEO who had recently turned around a low-cost carrier. Of course. 

But what's frivolous about serving passengers a meal on a three-hour flight, which usually involves quite a few hours' more of travelling by road and waiting at the airport (security, luggage)? Or giving them a seat slightly better than a school bench? Does adding a few more rows of seats or serving only peanuts and water enormously improve the low-cost carriers' chances? 

Or are these excuses - justifications - for the ability to charge realistic fares that business travellers are OK with (though they may not be pleased with)? 

By the way, is the casualty rate among low-cost airlines a great deal better than that among the 'standard-fare' ones? Low-cost probably doesn't translate into high-margin. If it indeed doesn't how do these people manage in lean times?