Chapter 11 is not a state subsidy. It is a provision of US law that allows a company to attempt restructuring - with the permission of a court.
There is no free lunch here - creditors, shareholders, employees get screwed. But creditors and employees may get screwed less than if the company simply closed shop in Chapter 7.
Imagine what would happen to the airplane leasing market if UA, US, ATA, Hawaiian went out of business. Now you know why GE, ILFC, Airbus, Boeing and others finance a lot of Ch11 proceedings, it is in their interest to see these airlines continue as a going business
As Glenn Tilton of UA pointed out:
166 US airlines filed Ch 11 since 1978, and only three came out of Chapter 11 as viable businesses.
Of the 15 largest US carriers in 1980, only five survived today.
In contrast, 11 of the largest 15 airlines operating in Europe 25 years ago are still in business.