In some markets, yes. But in most markets there needs to be some minimum acceptable standard of QC & assurance. In the market for aluminum tubes hurling through the skies at 500 mph it's to everyone's benefit to make sure they don't come crashing to the ground.
Even markets for more innocuous products/services require some minimum acceptable standard or else the race to the bottom will give us more affordable but more dangerous products: Thomas the Tank Engine ($3) vs Deluxe Thomas the Tank Engine with Lead-Free Paint ($5)
Which is what we already have at the consumer end of airline pricing. The economy seats on an airplane put together aren't enough to pay for the cost of fuel. Business and first class passengers are the only ones that make the airlines any money.
